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mrlegoman
02/07/2008, 10:04 AM
Our Vehicross is experiencing what I'm told is torque binding when turning a sharp corner. Can someone please explain this and how to fix it?

tom4bren
02/07/2008, 10:07 AM
What are the symptoms - tire chirp, bouncing, ... ?

mrlegoman
02/07/2008, 10:14 AM
It feels like the transmission is in super-low and the tire is rubbing on something (which it is not). After the car is straightened out, it's fine.

johnnyapollo
02/07/2008, 11:36 AM
Could be a few things - I experienced something similar when the TOD speed sensors went out on mine (the FWD was bascially disabled so it was pulling load during turns instead of driving the front wheels). What you're describing could also be bad CV joint(s) from my past experience with Hondas.

-- John

mrlegoman
02/07/2008, 11:53 AM
The wheel bearing are going bad too. Could bad wheel bearings lead to bad CV joints?

Joe_Black
02/07/2008, 11:55 AM
It's common for short-wheelbase vehicles to do this, and with only 90" the VX is firmly in that category. My Trooper RS did the same thing.

If you've got worn out steering/suspension components the added stress will make it more apparent.

ojmagg
02/07/2008, 12:07 PM
Mine has done this since 5k miles (when purchaced)

tom4bren
02/07/2008, 12:39 PM
I wouldn't say that bad bearings leads to CV joint wear. The bad bearings could certainly give you the symptoms you describe.

Bad CVs usually show up as a noise issue long before it gets bad enough to 'feel'. Clicking during coasting usually means the inner CVs are bad. Clicking during turning usually means the outer CVs are bad. Have you checked your CV boots? If you're not lifted & your boots aren't cracked or split & you don't hear any clicking noises (changing with speed) then your CVs probably aren't bad.

ZEUS
02/07/2008, 01:01 PM
Maybe try to adjust the steering lockout bolt so you can't turn as sharp? No idea otherwise.

CoastieCosta567
02/07/2008, 03:38 PM
Is your tTOD check light on?

Cuz if it it, then your rear and front speed sensors that are located on the TOD itself have gone bad, or dirty connectors, or broken wire, pretty much what JohnnyAPollo said. But if not, then I don't know.

mdwyer
02/07/2008, 06:00 PM
Our Vehicross is experiencing what I'm told is torque binding when turning a sharp corner. Can someone please explain this and how to fix it?

I wonder if you're seeing what I described as "Chirping"? When I asked about it, I was told it was pretty much normal. http://www.vehicross.info/forums/showthread.php?t=12036

etlsport
02/07/2008, 06:08 PM
how fast are you doing when you get this? every so often my ABS used to (when i still had ABS) kick on when i would make a wheels locked turn and touch the brakes at all the whole car would shudder until i released the brakes

mrlegoman
02/09/2008, 08:21 AM
Is your tTOD check light on?

Cuz if it it, then your rear and front speed sensors that are located on the TOD itself have gone bad, or dirty connectors, or broken wire, pretty much what JohnnyAPollo said. But if not, then I don't know.
After the post the other day, I was driving home and the TOD "CHECK" light began flashing at me. The display also showed no lights to the front wheels, which usually there is at least one. After about 5 minutes, it all went back to normal.
So is this indicative of having a bad speed sensor?

VXR
02/09/2008, 06:20 PM
Mine has done this since 14k miles (when purchaced)
it only does it when you turn max right or left...

mrlegoman
02/19/2008, 10:31 AM
Could be a few things - I experienced something similar when the TOD speed sensors went out on mine (the FWD was bascially disabled so it was pulling load during turns instead of driving the front wheels). What you're describing could also be bad CV joint(s) from my past experience with Hondas.

-- John
TOD Speed Sensors
Are these the same "Wheel Speed Sensors" noted in the shop manual?

johnnyapollo
02/19/2008, 04:30 PM
If I'm not mistaken the wheel speed sensors are at each wheel and feedback to the TOD ECU to determine when "slippage" is occuring - the TOD compensates by adjusting more power to front (back is always at "full"). The TOD speed sensors that went out on mine are both on the TOD unit itself - one in front and one behind the transfer case - these measure the speed the internal gears are running and also feedback to the TOD ECU so that it can adjust power to front.

-- John

mrlegoman
02/19/2008, 05:09 PM
If I'm not mistaken the wheel speed sensors are at each wheel and feedback to the TOD ECU to determine when "slippage" is occuring - the TOD compensates by adjusting more power to front (back is always at "full"). The TOD speed sensors that went out on mine are both on the TOD unit itself - one in front and one behind the transfer case - these measure the speed the internal gears are running and also feedback to the TOD ECU so that it can adjust power to front.

-- John
Are you talking about the VSS?
There is no listing of 'TOD speed sensor' in the shop manual. Of course a search on TOD brings up about 1000 results......

mdwyer
02/19/2008, 05:09 PM
TOD Speed Sensors
Are these the same "Wheel Speed Sensors" noted in the shop manual?

I'm pretty sure that the answer to that is 'no'. There are Wheel Speed Sensors at the wheels, but they are used for the ABS system. The TOD speed sensor is located on the prop shafts, if I recall correctly. It is closer to the tranny than the wheels.

johnnyapollo
02/19/2008, 08:04 PM
Makes sense.

-- John

mrlegoman
03/14/2008, 07:08 AM
I've located the Front and Rear Speed sensors.
4B2-4 in the shop manual.
But I cannot find a part number in the 'part list' for them.
We don't have an official local dealership. Where else can I look?

rocket man
03/17/2008, 01:48 PM
It sounds to me like what Johnny Apollo and other's have had including me (bad speed sensors)...

I just posted earlier today my transmission and t/c odessey. If I were you, I would check the wiring leading to these sensors first they get really close to the exhaust pipes.

I had a major transmission failure but I also had the symptom of what the manual calls "tight corner braking". This felt like a binding to me too... I lived with this for abount 6 months. I also had a "check TOD" light. Without out a code reader (special one from Isuzu) you are SOL. A dealer will read the code for around $85. I never got to the dealer to diagnose, I just swapped out a transmission and transfer case and the problem went away.

The front and rear sensor's are on the "Transfer case". These sensors are approx. $235 a piece, from Isuzu. In my travels on the net looking for a transmission, I found lots of transfer cases for the Trooper 2 99-2001 and VX 99-2001(these are interchangable and mirror image of themselves). I found one for $125.00 + $25 shipping and it had both sensors! They (transfer cases) ranged in price from $75-$350. That trims the cost from $470 to $150, plus you get a transfer case core in return to use for parts or exchange if you ever trash your present transfer case

The rear sensor is pretty easy to replace the one at the front is on top of the TC in a tight area. I did a straight r&r on trans and tc which entailed dropping the rear crossmembers and front and rear propellar shafts. Access to these places would be easy then. Try car-parts.com and follow the prompts and see whats out there. Dealers charge a lot to replace these, but its really easy especially if you have little hands.


Good lucK

John

Wylderon
03/31/2008, 04:47 PM
I have the same problem....turn sharp and starts binding.....tod light freaking out and sometimes you can hear a "Thump" in the rear end.......I am totally lost on this TOD thing.....sometimes it's working fine then sometimes its freaking Haywire!!! Have Read the threads on TOD but still lost......

rocket man
04/01/2008, 11:50 AM
"Tight corner braking" is a term the factory manual coined.

It best describes a malady that is associated with the function of the speed sensors. There are 2 of them and they are on the transfer case. One is up high on the right side of the case and is held in place with a nut and retainer there are wires leading from it to the ECM that controls the TOD. The same is true with the speed sensor in the rear to the TC (transfer case). Don't confuse this with the speedometer sensor that is on the right side also but looks way different and is adjacent to the propellar shaft.

But before, I suggest you run this test. Go into a market parking lot, or better yet a a place with nice shiney cement floor like an underground parking lot. Now while going very slow forward turn the wheel left or right to "full lock" does the car act like or feel like your applying the brakes? Also do you feel any sensation of "hard steering" that seems to let-off when the wheels straighten out?? Then does it relase with a "thud only to start braking again?

Okay that is "hard Corner braking". The popping or the "thud" is the "clutch pack" binding up and then releasing in the transfer case. We have full time 4 wd so it is necessary we syncronize the speed and distance that the front and rear wheels travel. For example, when you make a sharp right turn your right front wheel (inside)is traveling a much shorter distance that the left front wheel (outside). The same is true for the rear wheels. Those sensors syncronize the power to the front propeller shaft.

I you have any mechanical ability I would climb under the car with a high intensity led lite attached to your forhead and realy scrutinize the wiring and connectors that lead to your transmission and TC. Since your problem is "intermittant" and not constant....that could be a very real possibility. I would especially check the wiring area around the converter housing on teh left side of the transmission as it passes very close to the exhaust manifold, the wiring should go behindthe heat shield. Check that area real close.

Also, you didn't mention this but you should be seeing a "check TOD" lite in RED that is under the TOD meter. This will reset each time you turn the car off, but then show up again after driving a short distance. If you are not getting a "check TOD lite" your problem may be elsewhere??

If all else fails take it to a dealer that has the computer to shoot the "trouble codes". This is a different diagnostic computer than you can get at Kragen or at your local shop and from what I have been told it is only availble at a Isuzu dealership. BTW the sensors are around $235 each. (no labor) although they are not difficult to install I have heard quotes of around $600 labor.

You could solve this problem by purchasing a TC from a wrecking yard and scavaging the sensors ($125-$350) and instdalling them in your unit. Make sure before you buy that the sensors are there. Check: car-parts.com go the home page and follow the prompts.

Good luck:)

John
ps...download or purchase the CD manual for this car, available on this site, if you do not already have it. It will help you alot.......

psychos2
04/01/2008, 02:45 PM
have you checked the tire pressure? and how worn are your tires? shawn

mrlegoman
03/14/2009, 10:03 AM
The front and rear sensor's are on the "Transfer case". These sensors are approx. $235 a piece, from Isuzu. In my travels on the net looking for a transmission, I found lots of transfer cases for the Trooper 2 99-2001 and VX 99-2001(these are interchangable and mirror image of themselves). I found one for $125.00 + $25 shipping and it had both sensors! They (transfer cases) ranged in price from $75-$350. That trims the cost from $470 to $150, plus you get a transfer case core in return to use for parts or exchange if you ever trash your present transfer case

John

I've spent the entire morning searching the net and have not had much luck finding anything. The closest I've come to is parts.com:
Electrical - Powertrain control - Vehicle speed sensor $146

Does anyone have the Isuzu part numbers for these sensors? I cannot find them in the parts catalog.

But the 99-2001 Trooper 2 used the same transfer case and sensors as the VehiCross?
There are some VehiCross cases for sale on car-part.com. Lowest price seems to be in the $400 range. Not sure how much their going to charge for shipping.

So my choices basically are to either spend 300$ on two new sensors or spend $500 on a used transfer case with used sensors that might be ok?

rocket man
03/15/2009, 09:12 PM
So my choices basically are to either spend 300$ on two new sensors or spend $500 on a used transfer case with used sensors that might be ok?[/QUOTE]

You just searched under Vehicross....go back to car-parts.com and search under, 2001 Isuzu, Trooper 2. transfer case, then look for "with torque on demand" or w/TOD. It is the exact same tranny, transfer case, and sensors as your car.... all wrecking yards may not know this. I think the price goes up when they get in a car like the VX and they think its rare. I just visited the site and there were many t/c's in the $200 range with one listed for $150and another for $175. They were both in California, but these places will ship via truck cheap!

Revisit the site and you'll see....be sure to confirm that the sensors ands connector wires are still in place...

mrlegoman
03/16/2009, 05:10 AM
^ Thank you!! I appreciate the help!

rocket man
03/16/2009, 10:38 AM
Your very welcome Legoman::)

BTW. I might not have made it clear in my post but the transmissions, t/c and sensors on the Trooper 2 with TOD are the same in 1999-2002.

evillecutter
07/02/2013, 11:00 AM
ran across this old thread and thought i would input - this is what mine did when the chain in the transfer case stretched and the clutches went bad - according to borg werner our transfer cases are completely unique to the vehicross

Leon R
07/02/2013, 12:12 PM
"Unique" - as in: it has a different part number, but otherwise can be easily interchanged or...

As in: do not even consider substituting them!

A lot of people (aka manufacturer's reps) like to do things "by the book".

nocturnalVX
07/03/2013, 06:14 AM
I have had this issue since having my transfer case rebuilt... Looks like I have to bring the VehiCROSS back in.

:_brickwal

evillecutter
07/03/2013, 06:16 AM
they (and isuzu) said it has different gearing from any other vehicle and tod will not work properly buy you ar correct "they" would say that - either way its a pita

im pretty sure the guy from borg werner was just helping me because he wanted to know for himself and hadnt thought about a vehicross for a while - he was very helpful - isuzu, however, apparently only employs about 15 people total in the u.s. anymore and none of them seemed to happy about answering the phones

1999E
09/02/2014, 02:45 PM
Hello everyone,
I'm the original owner of my 1999 VX. I have enjoyed driving her off road, inclement weather, all surfaces, and she's performed admirably in every situation. But now due to age I suspect, despite careful maintenance, she's beginning to have some problems and it is only now I'm discovering how rare she is, and how advanced technologically she was for her time. May I ask if anyone has experienced sensor difficulties, that is she's trying to go into four wheel high when not required. Her torque on-demand system is not functioning appropriately and after much head scratching and computer code reading, my mechanics are suggesting sensor replacements --not only a throttle sensor but another slip/speed sensor is well. They say if I simply disconnect the four-wheel-drive capability, I will also lose ABS braking which sounds unsavory. Has anyone had to replace the sensors and if so what is been your experience? Thank you so much for your time.

Triathlete
09/02/2014, 04:08 PM
First things I would check are tire air pressure and tire wear. If the front or rear are off by even the smallest amount the TOD will act up.
If that don't work you may want to start a new thread since your subject is different from this one and it will end up getting overlooked and buried. Also the search function will yield you many threads to peruse through on the subject.

nocturnalVX
09/02/2014, 07:37 PM
It took a lot to get my VX working 100%, but it was worth it. I am not exactly certain what all went into the transfer case rebuild, but I do know they ended up replacing the speed sensors (and wiring harness/pigtails/whatever) to make the VX stop sending power up front unnecessarily. Now, my VehiCROSS can do U turns again!

mrlegoman
09/02/2014, 07:50 PM
Yes, new thread would be best. FYI, we have the same guts as a 99-2001 Trooper 2. So our engine and drive train is not as rare as the dealers and repair shops make it out to be. There is some debate on that subject too, but a used 2002 Trooper 2 transfer case fixed my torque-binding issue. ($550 and it included all sensors)

1999E
09/03/2014, 03:20 AM
Cool. Thanks very much, will investigate all recommendations above. If no success, will start new thread (sorry, learning a whole lot about my VX now, was blithely ignorant before-- only minor problems for the first 15 years! Sigh. )