Do these cars for a fact have an adaptive transmission control system for the 5hp24? I just got mine running again last night with a new clutch drum and everything is fine, but the downshifts are kind of harsh. I replaced torn o-rings on the A drum piston also. I didnt tear down the whole thing to remove metal chunks. Thanks in advance.

 

I think both the ZF trans and MB trans of the R cars are adaptive, the advice given here is to drive around switching from normal to sport once in a while - it should settle down.

 

It is my understanding that the 5HP24 is not really adaptive as much as it has 6 shift programs that it selects from based on all the inputs at any given moment.

 

This is what I was afraid of. Come to think of it, the bump during downshift may have been there before. It's my wife who primarily drives the car.

 

By 'downshifts' do you mean a throttle forced down shift or a coasting to a stop downshift? I had a TCM that refused to dump the torque converter lock up pressure on forced downshifts and caused quite a bump.

Don't mean to send you off on a wild goose chase.

 

I can feel it both ways. Coasting to a stop, I can feel each downshift as a slight bump. Adding throttle at low rpms induces a kickdown and I feel it then too. It seems to kickdown slightly harder while in sport mode. Of course, this could be expected since it is kicking down 2 gears instead of one.

 

Boy, I am pulling this out of my rear end but I remembered reading about a valve body issue causing uncommanded pressure spikes.

Never saw anything from Jaguar on this issue but here is a technical bulletin from BMW on the problem. Apparently linked to the A drum physical failure. Same transmission.

Sorry, not BMW but Automatic Transmission Service Group (ATSG) but found it on a BMW forum.

 

Whoa, this is definitely something to think about. I wonder how much $$ the valve is. I dont want to buy another valve body