Need Help: Drivetrain Whine, Slipping in tight turns

[bentcipher]

Hey everyone…

Got a little bit of a problem with my ’01 Vx with 95k miles in unfamiliar territory – searched the forum and it appears my issue is originating from within the drivetrain but I can’t get anything definitive.

SYMPTOMS:
The truck is “jumpy” in tight turns going slowly forward or backwards (whether left or right) – that is, when the steering wheel is locked in to the right or left, throttle pedal travel does not correspond to the usual rate of vehicle acceleration. It momentarily hesitates, as if you’re stepping on the brakes, then as it slightly lunges forward as if you release the brake, then brake again… so it’s rocking back and forth, and other times it feels like it “slipping” or similar sensation when ABS is kicking in. Feels very similar as if I had 4lo engaged and in tight turn but a bit more forceful in lunges which ruled traction-related issues out. Other than that, I don’t hear anything abnormal or hear/feel any grinding.

At the same time, I noticed another abnormality. The drivetrain (unsure where exactly noise is coming from) is A LOT louder than it used to be, especially as you’re coming to a stop. It’s exactly the same whine that you hear coming from your drivetrain except a lot louder. The vehicle does not feel different however, may slightly “heavier” if anything..

This may or may not be related but the Vx was towed about a month ago (this just started happening a week ago), which was done by a mistake and when the driver brought it back I asked him how he got the truck on his flat bed to which he replied that he used WD40 spray on the tires to drag it up from a asphalted parking lot onto a metal flatbed.

I’m looking for guidance on which component I need to start looking at (diffs, tranny, t/c, etc..) to resolve the jumping and the whine.

Also, I’d like to know if this is related to the “towing” method truck driver used few weeks before the problem surfaced.

Thank you all.

[circmand]

those threads sound similar to what you are describing. I hope this helps there are several suggestions

[4X4 UFO]

bentcipher,
I can't address all of your symptoms, but the whine on deceleration sounds a lot like the TOD does when all the tires are not the same circumference. I tried running rear tires that had about 3/32 less tread depth than the fronts, and it caused a loud driveline whine on deceleration. When I put an evenly worn set of tires on all the way around, the whine disappeared.

Randy

[bentcipher]

Thanks both for the reply... I checked the diesel sound search results... not it. I'll read it in more detail but so far the symptoms are different. The sound itself is an even whine that stays at about same pitch no matter what speed, acceleration, coasting, etc... also, this is not motor related. My gut tells me it's probably the differential but don't have enough experience to know for sure.

Oh, and it's definitely not the tires or traction related, same "whine" occurs whether I'm at 2 mph, 20mph, or 40mph... can't hear the rest due to wind noise.

As far as slipping/jumpiness in tight turns - I had this truck for about 3 years now and pretty familiar with its eccentricities and character traits, especially in tight turns, on/off pavement, good/bad tires. What I'm experiencing now is very dissimilar in a feel and sound.

Thank you both for the input.

[Solitude]

It is still an all wheel drive vehicle.... maybe your turn is a bit too tight for the speed

[bentcipher]

Well.. I think the culprit here is the front axle. For now, I'm ruling transmission and T/C out as I'm not able to establish a relationship between the symptoms and the transmission or gearing itself. The symptoms persist whether I'm in gear or coasting in neutral, forward or reverse, slow or fast, in 4lo or 2wd, etc..

I'm going to start with changing fluid both front and back and see where that takes me. Will post results as soon as I have them...

[bentcipher]

Glad I could help... Actually, I'm really glad your issues were fixed with the T/C oil change. I still remember that sinking feeling, thinking "****e, how much is this going to cost?" Keep those fluids changing at regular intervals and you should be good. If you recently got the Vx, change them all just to be safe!

Sweet! And let this be a lesson that most of the shops out there have no idea what to do with a Vx. Even when it comes to what seems like generally simple to diagnose issues. I let them do my wheels... everything else I do myself.

Good luck!