Diff or Wheel bearing noise?

[89Vette]

I've finally gotten to demo a couple of VXs during the past month. I was a little concerned after driving all three. Specifically, all of them seemed to have some drivetrain vibration.

I already posted about the first one (and how I decided to pass on it) in the VX Talk Forum. (I found out it had been put in a ditch.)

The other two have some similarity -- though there is a difference. One whines when you let off the accelerator. It's been lifted. My guess(es) on this one are either a drive-shaft alignment issue -- or -- the inner pinion bearing needs replaced. (Sound seems louder from the rear.) By inner pinion, I mean the one up at the nose. (Let me know if that's supposed to be called the outer bearing.)

The one I am most inclined to purchase also has wheel-bearing-like noise. From about 40mph, I can begin to feel vibration. By 60mph, it is fairly loud. Between 60-65, it annoyingly loud though the harmonics quiet somewhat by 70mph. I could see this being a wheel bearing or differential bearing issue. I also note it's louder when sitting in the back seat.

My search brought up a post where it sounds like this 4x4 system might be as prone to differential bearing problems as the Grand Cherokees I've previously owned. Though it doesn't have quite the same whine/growl as the JGC I'm used to, the sound seems fairly centered -- meaning it seems most likely to eminate from a differential (vs out on a wheel).

How can I figure out what's going on? Determining the extent of repairs needed, their cost, and/or the propensity for recurrence could make a difference in my decision to purchase one of these units.

Any feedback is appreciated!

Gregg

[Riff Raff]

Gregg--- My best advice is to KEEP LOOKING!!! Run away from those poor VX examples, as those irregular sounds are probably the main reasons they're up for sale. Those sounds you hear are not normal and are an expensive can-o-worms just waiting to be opened.

Be patient; the right VX is out there somewhere, and you'll immediately know it after a thorough test drive and a mechanic's inspection. Heck; it took me over 7 years to find mine, so just keep lookin'.:bgwb:

[89Vette]

Gregg--- My best advice is to KEEP LOOKING!!! Run away from those poor VX examples, as those irregular sounds are probably the main reasons they're up for sale. Those sounds you hear are not normal and are an expensive can-o-worms just waiting to be opened.

Be patient; the right VX is out there somewhere, and you'll immediately know it after a thorough test drive and a mechanic's inspection. Heck; it took me over 7 years to find mine, so just keep lookin'.:bgwb:

This isn't a thread asking advice to buy or not. (I would place that kind of thread in VX Talk.)

[wintermute]

FWIW, my recently acquired VX had a similar 'whine' when decelerating. A noticeable almost rubbing like noise when you let off the gas at low speeds, and seemed to be worse at higher speeds above 40 MPH.

I've dug around the site some and read a few posts on the topic. One of the first questions asked of me was if the tires were mismatched. My front and rear tires were not only different brands and tread patterns when I picked it up, but the wear pattern was very uneven due to severe misalignment and lack of rotation.

It was suggested to me that tires on the VX are critical to the TOD system functioning properly. If tires are severely mismatched or unevenly worn (as mine were) it can cause bad sensor readings and lead to trouble in the transfer case.

In many threads I read, users/owners tended to notice this noise more, or for the first time immediately after lifting their VXs and putting on larger tires/wheels.

I'm not sure exactly what the issue is, if there are multiple problems described here with similar symptoms but different root causes, or what the ultimate solution is, but in all cases I've read about tire condition, size, and lifts seemed to play a role in triggering or exacerbating similarly described problems.

I changed my tires out for a near stock 255/60/18 on an aftermarket 18x9 rim, and most if not all of the sound I heard when decelerating is gone. I'm not entirely convinced that there isn't a 'problem' still lurking under there somewhere, but the new wheels and tires appear to have minimized the symptom in my case.

In any event, I'm very interested to see what others have to add on this topic. When I first encountered the rubbing/whining sound there was a distinct vibration I could feel as well. I thought it could be anything from a bad CV or drive shaft to a problem in the transfer case. I guess I'm still a little skeptical that new tires and wheels have truly eliminated the problem, and wonder if the larger tires, wheels, and lifts or worn tires put more stress on an already weak component or if bad sensor readings and TOD settings are really the culprit here.

[lasturbo]

The one I am most inclined to purchase also has wheel-bearing-like noise. From about 40mph, I can begin to feel vibration. By 60mph, it is fairly loud. Between 60-65, it annoyingly loud though the harmonics quiet somewhat by 70mph. I could see this being a wheel bearing or differential bearing issue. I also note it's louder when sitting in the back seat.
Gregg

This symptom above for me and my 1999 was the differential. I was lucky to obtain a like new used one from Lisa (VX Crazy) and after installation, synthetic gear oil, and LSD additive, it was good as new.

[PK]

89Vette, as you probably know, drive train noise is very difficult to diagnose without hearing it personally. Also, some of us will tolerate higher noise levels as "normal" than others do.

Couple of suggestions -
1. There are 3 grease nipples on the rear drive shaft. If these are not lubricated it will cause a drive shaft vibration and noise that sounds centred. So your fix could be as simple as a dozen shots of grease.

2. Rear axle bearing noise is very distinct. It is a "whaa - whaa - whaa" noise and the frequency is directly linked to wheel speed. It also can sound centred if both wheel bearings are shot. Then the noise merges into the centre.

3. Diff bearings or gear noise is more of a definite whine and comes and goes at certain speeds, and depending on if the throttle is down, or you are just rolling along.

4. As previously mentioned, tyre matching and condition, and even tyre pressures, are super critical on these vehicles.

Without actually hearing the noise, that is about as much input as I can give.
Use this condition to drive the price down, or walk away and keep looking.
If you get the price down, and it ends up being an easy fix, that is your reward for taking the risk.

Good luck.

PK

[89Vette]

FWIW, my recently acquired VX had a similar 'whine' when decelerating. A noticeable almost rubbing like noise when you let off the gas at low speeds, and seemed to be worse at higher speeds above 40 MPH.

I've dug around the site some and read a few posts on the topic. One of the first questions asked of me was if the tires were mismatched. My front and rear tires were not only different brands and tread patterns when I picked it up, but the wear pattern was very uneven due to severe misalignment and lack of rotation.

It was suggested to me that tires on the VX are critical to the TOD system functioning properly. If tires are severely mismatched or unevenly worn (as mine were) it can cause bad sensor readings and lead to trouble in the transfer case.

In many threads I read, users/owners tended to notice this noise more, or for the first time immediately after lifting their VXs and putting on larger tires/wheels.

I'm not sure exactly what the issue is, if there are multiple problems described here with similar symptoms but different root causes, or what the ultimate solution is, but in all cases I've read about tire condition, size, and lifts seemed to play a role in triggering or exacerbating similarly described problems.

I changed my tires out for a near stock 255/60/18 on an aftermarket 18x9 rim, and most if not all of the sound I heard when decelerating is gone. I'm not entirely convinced that there isn't a 'problem' still lurking under there somewhere, but the new wheels and tires appear to have minimized the symptom in my case.

In any event, I'm very interested to see what others have to add on this topic. When I first encountered the rubbing/whining sound there was a distinct vibration I could feel as well. I thought it could be anything from a bad CV or drive shaft to a problem in the transfer case. I guess I'm still a little skeptical that new tires and wheels have truly eliminated the problem, and wonder if the larger tires, wheels, and lifts or worn tires put more stress on an already weak component or if bad sensor readings and TOD settings are really the culprit here.

I read that too. In your case, I think you'd be wise to mount four new, balanced tires to see what happens. But, mis-matched tires should exhibit problematic sounds under many conditions (vs just in decel). I don't think that's your "solution", but having four matched tires, will probably rid you of some road/tire noise.

FWIW, I asked a machine shop about this today. The head machinist told me how you could tell which of 1) the ring bearings, 2) outer pinion bearing, or 3) inner pinion bearings were failing.

If the sound occurs fairly evenly at all speeds, the ring bearings (aka carrier bearings) are probably going bad.

If the sound occurs under accelleration, the inner bearing (base of pinion) would be seeing the most pressure.

Otherwise, under decel, the outer bearing (nose of the pinion) would be seeing the most pressure.

[djvx]

my vx has the noise vibration upon de-accelaration since i bought it. It was bone stock, original tires, no mods, 50,000 miles. I took it back to the dealership and they did a service bulletin search and found nothing. They did nothing. I've since done an old man emu lift, torsion bar crank, bigger tires, a tranny flush, rear diff lube, greased driveshaft and put 15,000 more miles on it. Sound is there but has never gotten worse. Like I said earlier, it happens when de-accelerating and It was very concerning at first. But I now don't worry about it.

[djvx]

Otherwise, under decel, the outer bearing (nose of the pinion) would be seeing the most pressure.[/QUOTE]

What would the "fix" be for this- did the mechanic say?

[LittleBeast]

My noise at highway speeds when I let off the accelerator is getting almost unbearable. It seems to have gotten significantly worse the higher I lifted the suspension lift, greasing the grease points only seems to help for a day or so :(

[RamAirZ]

When I got mine it would always make a "whine" when decelerating under 40mph or so, almost like it was in low-gear and right before I would get to a stop it would just disappear, almost like something disconnected at a certain speed, would happen when you felt the transmission downshift before a complete stop. Since I put my manual hubs on I don't hear it anymore so I'm thinking it had something to do with the TOD and front axle.

[89Vette]

89Vette, as you probably know, drive train noise is very difficult to diagnose without hearing it personally. Also, some of us will tolerate higher noise levels as "normal" than others do.

Couple of suggestions -
1. There are 3 grease nipples on the rear drive shaft. If these are not lubricated it will cause a drive shaft vibration and noise that sounds centred. So your fix could be as simple as a dozen shots of grease.

2. Rear axle bearing noise is very distinct. It is a "whaa - whaa - whaa" noise and the frequency is directly linked to wheel speed. It also can sound centred if both wheel bearings are shot. Then the noise merges into the centre.

3. Diff bearings or gear noise is more of a definite whine and comes and goes at certain speeds, and depending on if the throttle is down, or you are just rolling along.

4. As previously mentioned, tyre matching and condition, and even tyre pressures, are super critical on these vehicles.

Without actually hearing the noise, that is about as much input as I can give.
Use this condition to drive the price down, or walk away and keep looking.
If you get the price down, and it ends up being an easy fix, that is your reward for taking the risk.

Good luck.

PK

New Falken tires are on the vehicle, so that's not it. Actually, you can hardly HEAR the problem sitting in the driver's seat. But you can certainly feel it. Vibration hits sensory threshold about 40mph. By 60, there's enough vibration, I could compare it to running a lawn motor. You can definitely hear it, but it's not that loud in the front. Vibration is the more relevant symptom from the driver's perspective. The vibration/sound is most prevalent under acceleration and holding speed. When the throttle is released, 20% of the vibration goes away. This is either vibration from the motor itself -- or vibration getting that power to the wheels. (It does not get louder under decel).

When I ride in the back seat, sound is considerably louder. It varies only with speed but does not oscillate. I'm not certain if this clinches the rear axle/diff as the culprit, or if harmonics of the vehicle/chassis trasmit more loudly in the rear of these cars. (Same is true for vette coupes.)

The entire drivetrain on all three I've driven have exhibited some degree of whine/vibration which makes me wonder how much is native to the TOD setup. OTOH, I'd find it hard to believe new vehicles were sold if they ALL sound/vibrate this way. The particular vehicle I'm interested in has been stored for the past two years and has less than 80k miles on it. There's enough "new" feel left, that I can sense what a new one might have driven like.

While old fluids could be contributing to the problem, it simply feels like there's harmonic vibration in the drivetrain. It doesn't oscillate, but it does vary with pitch/intensity with speed. It feels like a bearing issue.

Since it's much more pronounced in the back, I'd be inclinded to think rear diff. OTOH, I can clearly feel it in the SWheel. No fluids are leaking and the undercarriage looks very good for its age.

(What are the zerts in the rear drive shaft for? If "dry", whats the symptoms?)

On a side note: Do these have an air pump that's audible at idle/low rpms? Seems like I hear that too.

[etlsport]

doubt its the problem, but I have had problems with my rear diff building up pressure because the vent tube gets clogged, maybe check that?

for the zerk fitting, the only symptom ive noticed is a clunking during accel and decel from the driveshaft when they need to be greased.

if the bearings are going bad, you should be able to feel it by jacking up the rear wheels, holding the tires at 2/7 and pushing/pulling, then try 11/5.. then 3/9 there should be basically no play at all

[tom4bren]

Vibration with little to no noise = tire balance in my book.

Mine makes 'airbox noise' always has since I've owned it. Some gear noise has always been present too. It's hard to hear though since I'm running Wrangler MTRs.

[etlsport]

Vibration with little to no noise = tire balance in my book.


agree with that... my Falken tires have been a nightmare to get balanced properly.. ive had 3 different people try to balance them on 4 different machines, they are finally right.

[89Vette]

Vibration with little to no noise = tire balance in my book.

Mine makes 'airbox noise' always has since I've owned it. Some gear noise has always been present too. It's hard to hear though since I'm running Wrangler MTRs.

Little noise in the front. Lots of noise in the back. This should be categorized in the little to alot range,,,but your point is taken. I suppose sitting in storage could have an affect on tire integrity too. (Belt distortion/flat spots.)

Also, since I've been around the block a few times, I've driven vehicles that needed their tires balanced. This feels more like [hard] bearing vibration.

[Scott Larson]

My '01 has a whine from the rear diff under acceleration only, pointing to a worn ring and pinion to my way of thinking. The VX had 150,000 miles on it when I bought it so it is completely understandable! I've changed every fluid to the recommended viscosities with appropriate additives (read, "friction modifiers") all by Amsoil and things got amazingly quiet all the way around. Still a slight whine, but I'm not complaining. I wish she had come with all her service records, but alas, she was bought at dealer auction and had none. Somebody took care of her though...

[tom4bren]

This feels more like [hard] bearing vibration.

The only sure way to tell would be to check the fluid in both differentials, the transfer case & the tranny. Look for burnt smell or dark coloring & look for any metal shavings suspended in the oil.

I know, it's a lot to go through but if it has you worried enough, it'd be worth it.

[89Vette]

Today, I noticed there's some vibration as it's revved in park -- especially when cold. Though it's possible a tune-up (or injector service) is necessary, it's not really a miss. I'm still thinking bearing(s). I confirmed this by kicking it out of gear on the hwy too. The effect directly corresponds to engine revs.

Because I'm also hearing a bit extra noise at startup, I'm leaning toward an engine accessory bearing issue. It's [somewhat] reduced after warm-up.

[LittleBeast]

Looking through my old VX.info files I found something on this, maybe it will help:

ZEUS
Site Supporter 1999, black, VX, 1031
Salt Lake City, UT US
Member Since: Dec 2005
Posts: 1,474

Let me tell you, 4.77's make some noise! I figure my new mud tires will help mask that humming! And just the opposite of the first post... if you start to hear a racket when you take your foot off the gas when going down the highway, it could be the preload on your pinion is too tight or too loose. Either way, the pinion bearings create a lot of noise and a lot of heat when they are out of spec.

Green Dragon
Super VXer 2000 Dragon Green VX 0485
Virginia City Highlands Nevada, nv us
Member Since: Jun 2002
Posts: 380

A whine interpretation from Great Britain

"Usually a noise on accel or decel means a ring & pinion mesh problem. This generally requires diff replacement or rebuild. However if this is the case, they will go a long time with no problems other than the noise."
------------------
Phil Prince
ASE Master Technician
Factory trained
Jaguar & Land Rover Tech

Moncha
Administrator 2000 Proton Yellow 0584
Pueblo, CO US
Member Since: May 2002
Posts: 1,871



The pinion gear (Ring gear) can be shimmed to get rid of the noise. Unless something else is wrong with it.
rowhard
Site Supporter 2001, Dragon Green, 1342
Olympia, WA US
Member Since: Dec 2005
Posts: 951



Joe, I'll be honest, it could be as simple as a backlash adjustment that you can eliminate with shimming. BUT, it takes special tools for measuring and knowing what the heck your doing. Yes, any mechanic with the training, tools and spec's could do it, just finding one that would do it. Most just want to replace something, not repair it. And yes that is the name we call it. The British I believe call the ring gear a crown gear, can't remember what the call the pinion gear off hand. If you have the workshop manual downloaded into your home computer, it starts on page 334
MY2000 lsuzu Hombre



Gear Noise
Gear noise (whine) is audible from 32 to 89 kmlh (20 to 55 mph) under four driving conditions.

1. Driving under acceleration or heavy pull.

2. Driving under load or under constant speed - -

3. When using enough throttle to keep the vehicle from driving the engine while the vehicle slows down gradually (engine still pulls slightly).

4, When coasting with the vehicle in gear and the throttle closed. The gear noise is usually more noticeable between 48 and 64 km/h (30 and 40 mph) and 80 and 89 km/h (50 and 55 mph).

Bearing Noise
Bad bearings generally produce a rough growl or grating sound, rather than the whine typical of gear noise. Bearing noise frequently “wow-wows” at bearing rpm, indicating a bad pinion or rear axle side bearing. This noise can be confused with rear wheel bearing noise.

Rear Wheel Bearing Noise
Rear wheel bearing noise continues to be heard while coasting at low speed with transmission in neutral.
Noise may diminish by gentle braking. Jack up the rear wheels, spin them by hand and listen for noise at
the hubs. Replace any faulty wheel bearings.

Knock At Low Speeds
Low speed knock can be caused by worn universal joints or a side gear hub counter bore in the cage that is worn oversize. Inspect and replace universal joints or cage and side gears as required.

Backlash Clunk
Excessive clunk on acceleration and deceleration can be caused by a worn rear axle pinion shaft, a worn cage, excessive clearance between the axle and the side gear splines, excessive clearance between the side gear hub and the counterbore in the cage, worn pinion and side gear teeth, worn thrust washers, or excessive drive pinion and ring gear backlash. Remove worn parts and replace as required. Select close-fitting parts when possible. Adjust pinion and ring gear backlash.
MY2000 Isuzu VehiCROSS Workshop Manual Page 1

[wintermute]

Thanks for the great post, littlebeast. Some very good leads and info.

[nfpgasmask]

The other two have some similarity -- though there is a difference. One whines when you let off the accelerator. It's been lifted. My guess(es) on this one are either a drive-shaft alignment issue -- or -- the inner pinion bearing needs replaced. (Sound seems louder from the rear.) By inner pinion, I mean the one up at the nose. (Let me know if that's supposed to be called the outer bearing.)

I would say this whine you hear when you leff of the accelerator is almost certainly the CVs. When you lift a VX, the CVs get angled and you will ALWAYS here this sound. I am pretty sure everyone on this forum with a lift hears this sound when you let off the gas. It's nothing to worry about as long as your CV boots are ok and you don't hear any clicking.

Drivline vibration is something else however.

Bart

[LittleBeast]

I would say this whine you hear when you leff of the accelerator is almost certainly the CVs. When you lift a VX, the CVs get angled and you will ALWAYS here this sound. I am pretty sure everyone on this forum with a lift hears this sound when you let off the gas. It's nothing to worry about as long as your CV boots are ok and you don't hear any clicking.

Drivline vibration is something else however.

Bart

Haha, i don't have ANY CV's at the moment (both blew out and are totally removed) and I get the sound when I left off the accelerator really bad, I don't think that is it ;)

[89Vette]

Today, I noticed there's some vibration as it's revved in park -- especially when cold. Though it's possible a tune-up (or injector service) is necessary, it's not really a miss. I'm still thinking bearing(s). I confirmed this by kicking it out of gear on the hwy too. The effect directly corresponds to engine revs.

Because I'm also hearing a bit extra noise at startup, I'm leaning toward an engine accessory bearing issue. It's [somewhat] reduced after warm-up.

As I said, engine noise seems the primary cause. Remember my post asking about air pump noise? I took it by an Isuzu service facility today. Tech took a quick listen. Immediately, he said intake gasket(s) leak. I asked if that would account for roughness at 2500. He also said motor mounts could be part of the issue.

This could be a combo of all 3. A little gear noise, a little mount vibration, and an accentuation by the intake (to create an imbalance in cylinder power).

Are intake gaskets really a [common] problem on these? The tech said it was a problem in general with the 3.5L motor.

[technocoy]

Just my 2 cents, but I feel like in general that the VX has a certain roughness to it. I remember when I first got mine (25,000 miles) that I for the longest time was thinking there was a bearing or a gears, etc that may be worn because of a whine or rub sound i was hearing when letting off or under certain rolling conditions.

With it not getting any worse and having grown used to it, it now seems normal, but when I drive my wife's pilot or another, more "civilized" vehicle it becomes evident when I go back to the VX that it's a bit more beastly than other cars.

It's also a bit rougher and louder in the higher RPMs than other SUVs, etc.

So, I don't want to lull you into buying something that may have issues, but the fact you have heard the same thing in three different VXs has me thinking you are experiencing the same thing I did.

Even my best friends JGC seems quiet in comparison.

Throw some dynamat in it and call it a ride!!!

Good luck.

[89Vette]

Just my 2 cents, but I feel like in general that the VX has a certain roughness to it. I remember when I first got mine (25,000 miles) that I for the longest time was thinking there was a bearing or a gears, etc that may be worn because of a whine or rub sound i was hearing when letting off or under certain rolling conditions.

With it not getting any worse and having grown used to it, it now seems normal, but when I drive my wife's pilot or another, more "civilized" vehicle it becomes evident when I go back to the VX that it's a bit more beastly than other cars.

It's also a bit rougher and louder in the higher RPMs than other SUVs, etc.

So, I don't want to lull you into buying something that may have issues, but the fact you have heard the same thing in three different VXs has me thinking you are experiencing the same thing I did.

Even my best friends JGC seems quiet in comparison.

Throw some dynamat in it and call it a ride!!!

Good luck.

Ask yourself if people would have paid $30k for the level of roughness/vibration you're talking about. Ask yourself again if the problem might have occurred on yours before the 25k mileage point? Certain vehicles do have "characteristics". But engineering, parts, part failures, and other aspects play a part in the final result.

Generation 1 JGCherokee's definitely have a problem with their differential bearings. They are louder and fail in a high percentage of cases. If the result is normally vibration/loudness vs breaking down, people could come to the conclusion it's just a characteristic of the vehicle. To me, it was a problem.

Again, I'm imagining what a new specimen would have felt like. Whether this is primarily the intake manifold problem, wheel bearing vibration, differential vibration, or other drivetrain bearings, it's something that could be found and improved. Or,,,you could say "Eh...whatever."

FWIW,,,the Isuzu tech did say manifold gaskets were problematic on the 3.5L motor. Whether it's true and/or he was blowing smoke, I don't know. Guess I could do a search or post a thread on that topic.

Considering how much more forgiving injection might make manifold leaks, maybe it is an issue (with the VX)? The tech called the gaskets "cheap plastic". Maybe FelPro or some other manufacturer makes a better set. Regardless, I'm trying to decide/learn how likely a manifold leak could feel like a vibration vs a miss. Maybe at just the right amount of cylinder imbalance -- just short of a lean miss??? I did also note an idle very close to an outright miss when it gets hot. I suspect this is a real issue. (Maybe it explains why the mpg is so bad (worse) for some owners?)

BTW: Compared to other 4x4 setups/brands I've driven, this Isuzu design does seem to have it's share of gear whine/drag. When you let off the gas, you can feel the drivetrain dragging the vehicle slower than other 4x4 system (i.e., Quad-Trac II or AWD car). It has more of the character of a truck,,,big truck,,,maybe even a BEAST. Probably part of the reason for the "Little Beast" nickname. Had I not noticed the pronounced vibration in park revving the motor, I might have come to the same conclusion.

I also found a thread on fan bearings causing this problem. So there are multiple possibilities. There are also multiple perceptions that could be formed from verbal description vs actual 1st-hand experience of individual symptoms.

[nfpgasmask]

That's weird because I never ever heard this noise, but as soon as I lifted, it was there.

Bart

[technocoy]

Ask yourself if people would have paid $30k for the level of roughness/vibration you're talking about. Ask yourself again if the problem might have occurred on yours before the 25k mileage point? Certain vehicles do have "characteristics". But engineering, parts, part failures, and other aspects play a part in the final result.

Generation 1 JGCherokee's definitely have a problem with their differential bearings. They are louder and fail in a high percentage of cases. If the result is normally vibration/loudness vs breaking down, people could come to the conclusion it's just a characteristic of the vehicle. To me, it was a problem.

Again, I'm imagining what a new specimen would have felt like. Whether this is primarily the intake manifold problem, wheel bearing vibration, differential vibration, or other drivetrain bearings, it's something that could be found and improved. Or,,,you could say "Eh...whatever."

FWIW,,,the Isuzu tech did say manifold gaskets were problematic on the 3.5L motor. Whether it's true and/or he was blowing smoke, I don't know. Guess I could do a search or post a thread on that topic.

Considering how much more forgiving injection might make manifold leaks, maybe it is an issue (with the VX)? The tech called the gaskets "cheap plastic". Maybe FelPro or some other manufacturer makes a better set. Regardless, I'm trying to decide/learn how likely a manifold leak could feel like a vibration vs a miss. Maybe at just the right amount of cylinder imbalance -- just short of a lean miss??? I did also note an idle very close to an outright miss when it gets hot. I suspect this is a real issue. (Maybe it explains why the mpg is so bad (worse) for some owners?)

BTW: Compared to other 4x4 setups/brands I've driven, this Isuzu design does seem to have it's share of gear whine/drag. When you let off the gas, you can feel the drivetrain dragging the vehicle slower than other 4x4 system (i.e., Quad-Trac II or AWD car). It has more of the character of a truck,,,big truck,,,maybe even a BEAST. Probably part of the reason for the "Little Beast" nickname. Had I not noticed the pronounced vibration in park revving the motor, I might have come to the same conclusion.

I also found a thread on fan bearings causing this problem. So there are multiple possibilities. There are also multiple perceptions that could be formed from verbal description vs actual 1st-hand experience of individual symptoms.

Not hearing your specific issue it's hard to know.

As for paying 30,000 for the vehicle you bring up an interesting point. Point being that no, not many people were willing to pay that much and that led to brand new VXs on lots for low and mid 20s. It's a concept vehicle that earned a short run being hand assembled. It's not an infiniti luxury vehicle.

I would say that yes, it IS possible some damage occurred prior to 25,000 miles, but seeing as how I've put another 55,000 on it with no issues I probably would say "meh, whatever".

That's not the point though, the point is that I've driven at least 6 differenct VXs one of them showroom new and they all have a rough and tumble running demeanor.

Now that being said, mine isn't exceptionally loud as some have described, but it does feel harder than other vehicles I've driven and owned.

Keep in mind that despite the cost, this is a specialty halo vehicle. There are no cupholders, etc. This was expensive because it was limited and advertised as essentially a consumer rally vehicle. It wasn't expensive because it was a smooth ride. I mean, my wife won't even ride in it it's so rough and I have Nitto Street tires on mine.

I don't doubt that there is an issue necessarily, I just think that coming from other cars to the vehicross takes some adjustment. If you keep looking for a problem on different cars and can't seem to pinpoint it it may just not be a problem. I would have to think that after you have driven several and they all have the same thing it's probably not something specifically wrong as much as it is a characteristic.

I do think I've seen several posts on here about issues with the gasket as well. A search will most definitely turn something up there.

If it's driving you that nuts, it may just not be the car for you.

Good luck! I hope you find one. I love my VX more than some of my family members.

[wintermute]

I love my VX more than some of my family members.

Me too! :laughing:

[89Vette]

Family members are one thing....How bout your wife, girlfriend, or mistress? LOL

Seriously, anyone reading this thread, go start your VX. Slowly run rpms from idle to 2500rpms. Tell me if it stays smooth or gets rough. (If it gets rough, you'll feel it in the steering wheel and gas pedal.) To me, it feels like bearing vibration.

[lasturbo]

Rear Wheel Bearing Noise
Rear wheel bearing noise continues to be heard while coasting at low speed with transmission in neutral.
Noise may diminish by gentle braking. Jack up the rear wheels, spin them by hand and listen for noise at
the hubs. Replace any faulty wheel bearings.

Has any member "Replaced Rear Bearings" yet because there is nothing in the workshop manual how to do it (unless I am blind) and what special tools and/or presses are needed to get the bearings off the axle shafts.

[etlsport]

just looked through our vehicle repair program. there is a time listed to replace the rear wheel bearings (1.7 hours per side) but no instructions or even diagrams for it:_confused

[SilverBullet75]

Great question...
Anyone ever replaced the rear wheel bearings?

Also, has anyone ever had a read diff actully fail?
What does it do? Grenade?

thanks,
---JIM---

[Lucian08]

I was about to post about a vibration noise, and this post came up as a suggestion to review. After reading through it, I seem to have similar issues to at least one or 2 others. My situation being that I have no noise until I hot about 40mph; after that there seems to be a vibration noise under acceleration or maintaining speed. No sound when letting off on the gas, and no sound under 40mph no matter driving style. One extra nugget of info is that I had this noise (or what I remember being this noise) both on acceleration AND deceleration; I hadn't driven in a couple months and just installed a diff drop (been sitting in the garage for far too long) and now the sound only seems to be as described above. I thought it may have been the CVs (and I had wanted a diff drop), but now I'm sure it must be something else. Front Diff? Rear Diff? I'll have a passenger drive with me this week to see if its coming more from front or rear, but the fact that it did change somewhat after the diff drop leads me to believe it is front related. Thoughts? The last post ended with the question of anyone actually having to replace a wheel bearing or diff; has anyone? Noise come or go after such a repair or upgrade?

[djvx]

I was about to post about a vibration noise, and this post came up as a suggestion to review. After reading through it, I seem to have similar issues to at least one or 2 others. My situation being that I have no noise until I hot about 40mph; after that there seems to be a vibration noise under acceleration or maintaining speed. No sound when letting off on the gas, and no sound under 40mph no matter driving style. One extra nugget of info is that I had this noise (or what I remember being this noise) both on acceleration AND deceleration; I hadn't driven in a couple months and just installed a diff drop (been sitting in the garage for far too long) and now the sound only seems to be as described above. I thought it may have been the CVs (and I had wanted a diff drop), but now I'm sure it must be something else. Front Diff? Rear Diff? I'll have a passenger drive with me this week to see if its coming more from front or rear, but the fact that it did change somewhat after the diff drop leads me to believe it is front related. Thoughts? The last post ended with the question of anyone actually having to replace a wheel bearing or diff; has anyone? Noise come or go after such a repair or upgrade?
Have you replaced diff fluids & transfer case and trans fluid lately? Greased the driveshaft? Sounds to me like normal noisy vx drivetrain, but my best reduction of the vibration was greasing the driveshaft, definitely helped. Tons of threads on vibration but Id do the fluids if you haven't lately. The vibration could be a driveshaft balance issue. Maybe you dented it?

[Lucian08]

I drained and replaced the front diff fluid when I did the drop last weekend. I'm gonna grease the driveshafts (is that as easy as it sounds?) and change the oil in the rear diff hopefully this weekend. The noise has slowly increased over time, so I doubt the shaft is dented but I'll give it a once over when I'm under there. If all else fails I'll just get a louder exhaust and hope it doesn't explode before my next upgrades.

[MSHardeman]

It really is that easy to grease the drive shaft (if you have a grease gun). There are three zerk fittings on the rear drive shaft. One at the front u-joint, one in the middle of the drive shaft at the slip joint, and one at the rear u-joint at the rear end. Plug your grease gun onto the zerk fitting and pump grease in until it starts oozing out of the u-joints/ slip joint. Actually, keep pumping grease in until the grease that is oozing out of the joints is clean. Wipe off the excess grease or it will get flung around under the VX and you're good to go.

One word of advise; wear eye protection and don't lay right under the joint that you are greasing. The eye protection is to keep all of the grit that will fall off of underside of the VX out of your eyes and you don't want to lay under the joint because the grease will fall off as it keeps oozing out and that stuff is really tough to wipe off of your skin (or hair).

[Mile High VX]

One word of advise; wear eye protection and don't lay right under the joint that you are greasing. The eye protection is to keep all of the grit that will fall off of underside of the VX out of your eyes and you don't want to lay under the joint because the grease will fall off as it keeps oozing out and that stuff is really tough to wipe off of your skin (or hair).

How knowest thou this?

:smilewink:bgwo::bgwb:

[MSHardeman]

Let's just say that I didn't need any hair gel for a couple of days. Had that 50's greaser look going for a while AND my eyes were all red from the dirt. It was a GOOD look.:eek:

[djvx]

I drained and replaced the front diff fluid when I did the drop last weekend. I'm gonna grease the driveshafts (is that as easy as it sounds?) and change the oil in the rear diff hopefully this weekend. The noise has slowly increased over time, so I doubt the shaft is dented but I'll give it a once over when I'm under there. If all else fails I'll just get a louder exhaust and hope it doesn't explode before my next upgrades.

Any update on that vibration?

[Lucian08]

Has it really been a month? Gawd I suck. Anywho, I had checked under the VX a few weeks ago and didn't see any fittings, but after checking the VX manual it agreed that they should be there (never should've doubted!). I FINALLY looked again last night and there they were; covered in crud but def there. Greased em until grease started to come out as suggested. Unfortunately the one on the rear joint has been dented so I'm gonna look for a replacement, but took it for a test drive and the noise is 95% gone! It was too easy! I'm gonna grease everything!

On an unrelated noise issue coming from the fan, I removed the four screws holding the blower under the dash on the passenger side and instead of finding a busted fan there were just a few leaves in there. Leaves gone, noise gone. Other than the whine of my 33" Nitto Grapplers on the pavement my Erebos is as silent as before. I took my sweet time and you guys were helpful as always. Now its time to get my skid plates on and head up to Gilbert, MN in a few weeks. Thanks again!

[HuzpazA]

FWIW, my recently acquired VX had a similar 'whine' when decelerating. A noticeable almost rubbing like noise when you let off the gas at low speeds, and seemed to be worse at higher speeds above 40 MPH.

I've dug around the site some and read a few posts on the topic. One of the first questions asked of me was if the tires were mismatched. My front and rear tires were not only different brands and tread patterns when I picked it up, but the wear pattern was very uneven due to severe misalignment and lack of rotation.

It was suggested to me that tires on the VX are critical to the TOD system functioning properly. If tires are severely mismatched or unevenly worn (as mine were) it can cause bad sensor readings and lead to trouble in the transfer case.

In many threads I read, users/owners tended to notice this noise more, or for the first time immediately after lifting their VXs and putting on larger tires/wheels.

I'm not sure exactly what the issue is, if there are multiple problems described here with similar symptoms but different root causes, or what the ultimate solution is, but in all cases I've read about tire condition, size, and lifts seemed to play a role in triggering or exacerbating similarly described problems.

I changed my tires out for a near stock 255/60/18 on an aftermarket 18x9 rim, and most if not all of the sound I heard when decelerating is gone. I'm not entirely convinced that there isn't a 'problem' still lurking under there somewhere, but the new wheels and tires appear to have minimized the symptom in my case.

In any event, I'm very interested to see what others have to add on this topic. When I first encountered the rubbing/whining sound there was a distinct vibration I could feel as well. I thought it could be anything from a bad CV or drive shaft to a problem in the transfer case. I guess I'm still a little skeptical that new tires and wheels have truly eliminated the problem, and wonder if the larger tires, wheels, and lifts or worn tires put more stress on an already weak component or if bad sensor readings and TOD settings are really the culprit here.

i just got mine yesterday and noticed the same type sound and also noticed it has 4 different tires all together on it. the sidewalls read:
front right) 265 70r16 111t
front left ) 265 70r16 112s- this tire is noticeably larger than the other 3
rear right ) 255 70r16 111s
rear left ) 265 70r16 109s

wtf, really? bought from a dealer this way, i can only hope it hasent been driven like this for a long time, very disappointing.
im going to check with some used tire shops around and see if i can trade these in towards the purchase of a full set of proper 245 70 16, im unsure about which T or S are needed tho