transfer case fluid
 

I have a 04 4.4. since I have owned this car (7 months) it has been having tranny problems. mostly when cold the trani would slip and create a hard thud,almost as if being rear ended. bmw has reprogramed or upgraded the software the 1st time at the dealer. on the 2nd visit for the same thing they replaced the mechatronics(have no idea what that is). Now on its third visit (technically 4th visit, they denied any problems on the 1st visit) they said BMW had a bulletin out for the transfer case fluid. they replaced the fluid (SIB-27-01-07 vtg fluid is what my reciept says). the car is a CPO and still under warranty, they told me it wasnt covered but they would do it under good will since the car has been there so many times for the same thing.

Has anyone had this problem? the car only has 46000 miles. what exactly is the transfer case? thanks in advance.

The transfer case is where the power is divided between front and rear wheels.

You didn't say if the fluid change fixed the problem or not?

Just got the car back a Lil while ago, so it remains to be seen if the problem was fixed.

look under the left rear seat, disconnect the module, this is the vtg module, drive the vehicle in failsafe mode, does it feel like it still being rear ended? if it does not, replace the transfer case underwarranty.

Transfer case is a big aluminum box with the transmission input going in and two driveshafts going out: one to the front 3rd member, and one to the rear. It splits the power from the motor to go to two sets of wheels at opposite ends of the vehicle instead of just one set at the rear.