Americas Transmission Programming and clunking

[Zimm]

It appears to me from driving more than one example, in high range the transmission is programed with gear holding/shifting, and tq converter slip such that for everyday street use the unit behaves in an unrefined and abrupt manner unconducive to smooth driving when stopping or in traffic. This increases with both positive and negative pitch of the nose, perhaps as an effort to control speed on hills, but with an aggressiveness that is excessive for dry pavement use, with the side effect of droning and poor 3-2 downshifts eliciting an unnerving clunk from the transfer case not experienced in other modern automatic SUVs.

Can you update the shift programming to eliminate these issues.

Please Advise.
Thank you.

 

[Zimm]

I still feel it is the t-case preload. This could explain why on a few of us have the issue.

preload ought to be more shifts, and easily repeatable. its the It's the 1-2 clutch engaging with the tq converter not slipping. I'm sticking with that.

 

[Tom109]

its the It's the 1-2 clutch engaging with the tq converter not slipping. I'm sticking with that.

I don’t know enough about the trans inner workings to reply.

 

[Simon C]

My Petrol gives the odd clunk (seems to be from the transfer case) but only when coming to an abrupt stop or starting to accelerate then having to stop again. Otherwise the transmission is so smooth you can barely notice it change.

 

[C-Mack]

I have the occasional clunk/chunking noise on 3 to 2 downshift and it was very noticeable when brand new for the first few months but now very rarely does it do it even in stop and go traffic.

I’ve found it helps to come off and on the throttle as smooth as possible like driving an old Land Rover with a worn out transfer case input shaft before they fixed the lubrication issues. Just another way driving the Grenadier reminds me of my old Land Rovers.

I suspect the transmission adaptations in the software get used to your driving style over time and mileage unless you treat the brake and throttle like on/off switches. It still happens now and then so hopefully IA takes notice and can tweak the software a bit to smooth things out further.