Excessive whine and front end vibration after installing TOD-off switch

[HeckaTrebeka]

Hey guys,

So... I know that there have been people saying that it's not a good idea to install a "TOD-off" switch, and of course I felt like I just had to install it because my TOD was kicking on from the spare tire that I'm running on it while I wait for a new tire that matches the other 3 I have on it right now.

Well I guess I must have made a huge mistake and turned something that was slightly annoying to pretty concerning. I installed the TOD-off switch and noticed that, since then, my VX was running on just the rear wheels - which was fine by me because that's what I wanted - but I also didn't notice anything kicking in when I would push the switch button. So I decided to try shifting into 4L(while in neutral), heard a big ol clunk when I put it into drive, and could definitely hear all 4 wheels moving.

I put it back into 4-Hi and ever since then, I get a front end vibration when moving slowly(>5 mph) and a pretty loud and high pitched whine when moving at faster speeds. I also noticed that if I'm backing up and turning sharply, the VX will stop if I let my foot off the gas to coast backward... This is very concerning and I hope I didn't screw myself over by installing that TOD switch. I bypassed that switch and hooked up the wires so that the ECU was connected as normal and am still experiencing the same issues.

I've searched around the forum for a similar issue but can't find one. If anybody knows about this or knows a previous thread for the same issue, please let me know.

Thanks!

[Gussie2000]

Didn't you know that the TOD is not switcheable so to speak ?

The vehicross is a FULL TIME 4WD vehicule,unless you swap all the drivetrain there's no switch that will "FIX" the vehicule runnning on all wheels because running on all wheel is part of the vehicule profile.

If you gonna drive a VX you got to accept the fact that you can't mess around with it

What you probably did is messing the TOD front sensors,now find out how much they cost to replace them

[VXorado]

If the TOD off switched is installed correctly, there is no reason why it would cause any issues. Seems like the problem arose when you put the T-case in 4lo. The big clunk was probably the drive shaft if you haven't greased the zerks recently. Do you have manual hubs? You need them to properly disconnect the 4wd with a TOD off switch.


(if you have manual hubs) I would start by pulling the pigtail on the TOD ECU. That will ensure its not transferring power to the front and you can see if the issue continues.

[HeckaTrebeka]

Would the sensors be responsible for the vibration? Could they be causing the TOD system to only be partially engaged? I've only owned this one for a few days, and have never owned another AWD vehicle before so I have no idea what malice I have caused.

[VXorado]

Would the sensors be responsible for the vibration? Could they be causing the TOD system to only be partially engaged? I've only owned this one for a few days, and have never owned another AWD vehicle before so I have no idea what malice I have caused.

If a sensor goes out, it will shut TOD off.

[MSHardeman]

Hecka, from what you are describing it sounds like the VX is still in four low. I know that when I put my VX in four low there is definitely more driveline noise, and it gets hard to make sharp turns, forwards or backwards.
Try putting it in neutral, shift back into four low, put it in reverse and back up a few feet to make sure that everything is engaged. Put it in neutral again and shift back into four high, making sure that the low/high stick is fully engaged in the high gear. Drop it into reverse and back up a few feet again to make sure that everything in the transfer case has released.
I've had a few instances where the VX didn't completely disengage out of four low and I had to re-shift it to get it to release.

[HeckaTrebeka]

Thanks MSHardeman I'll try that and let you know how it goes.

[HeckaTrebeka]

I just tried what you suggested, but turning sharply still makes the VX come to a stop and the whining noise is still happening... I dunno, I've heard of cases where it gets completely fixed just by putting all the same tires on the car. I'll see what happens if I directly wire the TOD system to the resistors and then report back.

[PK]

I dunno, I've heard of cases where it gets completely fixed just by putting all the same tires on the car.

I think this is your main problem from the start, and mucking about with the TOD wiring has now introduced another problem.

I suggest you put the TOD wiring back exactly as if was, and get your tye replaced.
Just for interest sake, what is the size difference between the 3 tyres, and the spare??

These TOD systems have been known to play up just because tyre pressure is down a little bit on one wheel. With a different OD tyre, all hell breaks loose.

Good luck.

Oh - and welcome to the forum.

PK

[Triathlete]

In ADDITION to what PK said you might want to unplug the TOD computee and the battery for 10 minutes to let all the computers reset.

[JMNY]

If you have driveline vibrations, take a look at this.
18.6 MB, 10:25 - http://www.drivehq.com/file/df.aspx/publish/mgpa/techvids/drivevibs.rm

[blacksambo]

If the TOD off switched is installed correctly, there is no reason why it would cause any issues. Seems like the problem arose when you put the T-case in 4lo. The big clunk was probably the drive shaft if you haven't greased the zerks recently. Do you have manual hubs? You need them to properly disconnect the 4wd with a TOD off switch.


(if you have manual hubs) I would start by pulling the pigtail on the TOD ECU. That will ensure its not transferring power to the front and you can see if the issue continues.

This is incorrect advice. The Vx TOD cannot be disengaged due to the internal ball ramp mechanism, or mechanical link.

I wonder where this fellow put the spare? if it's on the rear end that's incorrect, as well, it will screw up everything. Let's find that spare-mounting position out first and go from there.

[VXorado]

This is incorrect advice. The Vx TOD cannot be disengaged due to the internal ball ramp mechanism, or mechanical link.


What's incorrect? That you need manual hubs to disconnect the axles?

Fact: TOD off switch + manual hubs = no power to front wheels

4x4 is disconnected even if the front driveshaft still turns with no load. I don't think it's the correct way to use the TOD but it still works.



I wonder where this fellow put the spare? if it's on the rear end that's incorrect, as well, it will screw up everything. Let's find that spare-mounting position out first and go from there.


um... what? ;wtf;

[PK]

I wonder where this fellow put the spare? if it's on the rear end that's incorrect, as well, it will screw up everything. Let's find that spare-mounting position out first and go from there.

This has been mentioned on here before, but I just checked my owners manual, and there is no mention of it.
I think it is good advice, as the different diameter will make the rear Limited Slip Diff work overtime, and could cause longer term problems if left on for too many miles.
But I do not think that it would affect the TOD any more than putting it on the front.

Of course, that is a free opinion, and we all know what they are worth.

PK

[blacksambo]

What's incorrect? That you need manual hubs to disconnect the axles?

Fact: TOD off switch + manual hubs = no power to front wheels

4x4 is disconnected even if the front driveshaft still turns with no load. I don't think it's the correct way to use the TOD but it still works.




um... what? ;wtf;

Who said this fella has manual hubs, he only owned the VX for a few days???? Besides with manual hubs one would not a need a TOD off switch.

[VXorado]

Who said this fella has manual hubs

Running TOD off without manual hubs could have caused the issue. The front axles/wheels turning the driveshaft? Doesn't seem like that would be good for the t-case. :_confused

[vt_maverick]

I'd worry about running manual hubs without a TOD switch. What happens when TOD tries to shift power to the front wheels when the rear wheels are breaking loose? I would think you'd lose power to the rear wheels while not gaining traction up front which could lead to a loss of control.

Just a thought.

[Triathlete]

I have been running manual hubs without a tod switch for the paat couple years with no problems. No different than driving any other rear wheel drive vehicle.

[blacksambo]

I'd worry about running manual hubs without a TOD switch. What happens when TOD tries to shift power to the front wheels when the rear wheels are breaking loose? I would think you'd lose power to the rear wheels while not gaining traction up front which could lead to a loss of control.

Just a thought.

I like this thought, in snow/ice conditions etc.

[Scott Larson]

Hmmmm, sarcasm...

[blacksambo]

Hmmmm, sarcasm...

Absolutely not! I think he' s got a point there.

[HeckaTrebeka]

Hey guys, so I just got back from my camping trip... Thanks for all the responses! I decided to take the VX with me on my trip because the vibration went away and it was starting to go back to normal. I noticed that when I was on a hill at a stop light and going upward, I hit the gas and then the whole issue just went away... really perplexing. I'm thinking that the issue had to do with the 4Lo not being completely disengaged as was previously mentioned in this thread. Along with that, there is no vibration or whining noise anymore. I'm going to look into the front end before I ever use 4Lo again just to make sure it's lubed up good.

I don't have manual hubs as this VX is bone stock. I just thought that, by adding the switch, it would take care of the pulsing feeling. I don't think that this TOD switch really did anything though, as I found out that the switch was incorrectly wired in the first place and was still only connecting the blue wires together anyway.... hahaha.


Just for interest sake, what is the size difference between the 3 tyres, and the spare??

I believe that the spare I have on here is about 1/2 to 1 inch smaller than the rest. Plus, the tire place installed it on the rear passenger side... I asked them if it would be a better idea to install on one of the front sides because of the TOD system but they said no.. They were the stupid ones in the first place to puncture the original tire...!!

[MSHardeman]

Glad that it worked itself out.....sort of. It does sound like you where stuck in four low, and that when you were on the incline some things finally disengaged and dropped back into four high

For future reference I have read somewhere here on the site that it is best to put a spare, or different diameter tire, on the front of the VX. If the two back tires are a different size the TOD system reads the different speeds of the tires (due to their differing diameters) as wheel slippage and pushes power to the front wheels to stop that slipping. Since the wheels aren't really slipping, just turning at different rates, the TOD will continue to read that and continue to push power to the front wheels. When the TOD shifts power to the front wheels it really isn't a constant power, it tends to "pulse" the power forward. This pulsing is what creates the jerking motion that some describe when they talk about the TOD freaking out.

If you ever have to put a spare on your VX, and it's one of the rear tires, the best thing to do it to take one of the tires off of the front, place it on the rear, and put the spare on the front. PITA, I know, but your TOD will be much happier until you can figure out a more permenant fix.

[vt_maverick]

For future reference I have read somewhere here on the site that it is best to put a spare, or different diameter tire, on the front of the VX.

I believe this is what the owner's manual recommends, although it doesn't go into why.

[Triathlete]

It is also a good idea to find a dirt area a couple times a year and engage the 4l and drive around a little. If the system had never been used before by the previous owner that may have contributed to it sticking and not fully disengaging.

[Triathlete]

I believe this is what the owner's manual recommends, although it doesn't go into why.

Yep, its either in the manual or on the spare...don't remember which.

[blacksambo]

It is also a good idea to find a dirt area a couple times a year and engage the 4l and drive around a little. If the system had never been used before by the previous owner that may have contributed to it sticking and not fully disengaging.

Good advice, here.

[samneil2000]

I think putting the spare on the back has more to do with the limited slip diff in the rear where the front is open. I believe TOD only senses slipping at the rear axle and not side to side. I've been wrong once or twice though. ;)

[HeckaTrebeka]

I think putting the spare on the back has more to do with the limited slip diff in the rear where the front is open. I believe TOD only senses slipping at the rear axle and not side to side. I've been wrong once or twice though. ;)

I definitely agree. I kept asking the original owner this and he had no idea... he wasn't super into vehicles anyway, he just thought this one looked cool and unique(which, YEAH). Anyways, the tire company(who punctured one of the tires and started this whole mess) said that the spare should never be on the front... I was thinking the opposite because of the TOD system and I asked them about it. I guess I should know better than to ask a dummy a question.