Hey,

I notice when coming up to a light I feel a thumping once only usually. Tossing it in neutral and slowing makes no difference which leads me to believe it’s not tranny.

anyone know what this is?

4600km on the vehicle!

thanks in advance

 

TTT,

 

Are you running in 2Hi or in 4A? Sometimes, if there is no load on the front drivetrain, there can be some backlash that gets taken up as the vehicle comes to a stop. Whichever node you’re normally using, try using the other.

If you have the standard ESOF case, I assume you’d be driving in 2Hi. You can try shifting to 4Hi and slowing down the same to see if the problem persists. (Though if you use 4Hi on pavement, make sure you only go in a straight line or almost straight line. Shift back to 2Hi as soon as the rest is over.)

 

Thanks for the reply. I generally drive in ECO, so 2H is hilighted. I also have 3:55 Limited Slip. So you think I should try 4H and see if it still does it? Then report back?

 

It might be worth a shot. While it does not solve your issue to do so, it might give you a clue as to if the clunk is related to the 4WD system.

Ideally you would perform the test on a lower traction surface, such as a gravel road or wet road, but you can use 4Hi on pavement for a brief period provided you are only going in a straight (or nearly straight) line. Be sure to shift out of 4Hi before turning.

If the clunk does indeed go away in 4Hi, it could potentially be something in the transfer case or EIWEs creating the noise. If it does not, it is more likely related to the rear driveline or the transmission.

As for the limited slip - do you mean you have an electronic locking differential? As far as I know, no rear limited slip differentials are offered from the factory. The only factory LS offered is the front Torsen differential, which is an option only in Tremor and Raptor models.

 

Thanks again, I was out earlier and I can notice it more in Neutral coasting to a stop - right when it at about 99% there is a clunk. Has to be the rear end it's where I feel it. I paid $500 for Electronic Lock 3:55 Axle.

I'll toss it in 4H and do the coasting thing as it's almost 100% of the time.

FYI - Pitts is one of my favorite cities (as long as I am in an automatic). I'm there at least once a year visiting friends. He owns "Steel City Drones".

 

It acts the same way in 4H as it does in 2H. It's a single klunk right when you come to a stop. In gear it's a bout 50% of the time and in Neutral pretty much 100%

There must be a TSB or recall on this no?

 

I'm nnot aware of any particular TSB. Assuming you're still under warranty, I would consider asking the dealer to look at it.

You can ask about doing the "transmission relearn procedure" and see if that helps. The transmission is supposedly adaptive to change to the way individual people drive, and sometimes it can mislearn if people are also learning the transmission at the same time. A reset basically starts it fresh, and allows it to learn all over, but after you've already adapted your driving style.

 

Thanks again, yeah, its 2 months old, only!