Troubleshooting Transmission Issues - 2002 4.4

[jcp240z]

Look up the member RRPhil. He does rebuild these units as a hobby and has provided a lot of advice on both here and on the rover sites (they use the same transmission). He hasn’t been on in 4 months but you could send a private message to see if he is still around.
Also, do some searches on Google for Xoutpost Transmission RRPhil. You’ll find a lot of great information and insight Example https://xoutpost.com/bmw-sav-forums/...lipping-2.html

[upallnight]

Originally Posted by tempest411

I had the same thoughts with troubleshooting the transmission in the '03 I bought last month. I was disappointed to find a lack of tried and true methodology in testing for faults in these transmissions. I was told a lack of pressure testing ports was the reason for this.. So a lot of work done on these seems to be by using the Force or something. In my case I just gave my X to an experienced shop for a rebuild. I will pick it up tomorrow. I hope I like the way it drives and all...my experience with these vehicles so far has been limited to driving up behind several tow trucks, which has been the only way it's been able to get from one place to another:P

Unlike old transmissions that just utilize check balls in the valve body to direct the flow of hydraulic pressure to the clutch packs, the modern transmission utilizes a computer to direct the pressure through solenoids to the various clutch pack. You can verify the operation of the clutch pack by removing the mechatronic valve body and utilizing air to check for operation of the clutch pack as well as leakage. Of course, this would entail quite a bit of mechanic time as well as disposable such as ATF fluid, gasket, etc.

Here's a video on how a transmission is air checked.

https://www.youtube.com/watch?v=5LqRYaFxGw0