Hi Fellow Jeep Lovers,
I apologize if this subject has been trashed about here in the Forum...I don't want to beat a dead horse so to speak.

Kind of in a quandary RE Our 42RE Tranny...Our Jeep ZJ 4.0 has 232K on the clock and shifts Great including the OD shifting into and out of Lock-Up and the bottom of the tranny case looks quite new for a 1996!...Should We just do a flush of the 42RE and not crack the case or do a standard filter and fluid change (knowing that only about 50% of the old fluid gets replaced.) But does not "flushing" just run the nasty debris and fluid though the tranny and what about the filter?
I have had a umber of people including Mechanics say take it to Ammoco and just have Them do Their "Flush"...but how does that work with the dirty old filter in there?

I really like the idea of doing the filter, putting on an OEM "Rubber"-type pan gasket, and replacing the governor pressure solenoid and sensor, and the overdrive 3-4 accumulator return spring.
My wife and I are on a pretty fixed budget so cost containment is kind of crucial, But we both feel that Preventative maintenance is very important.
So far it is showing no problems shifting both up and down and the shifts are not hard or lazy...
Any ideas or suggestions would be much appreciated.
Thanks in Advance,
DocH and Willow

 

Drop the pan, change the filter and adjust the bands while you are in there, then refill it with ATF+4. Don't do a flush.

 

First of all stay away from Aamco! Nothing but a horror show.

What I did with my 2000 WJ 42re was do a fluid drain and filter change using the premium neoprene reusable gasket with no sealer, then change the fluid twice in the next 6 months. That gets the old fluid concentration down to about 12% at the most. I did not adjust the bands ever and replaced the transmission with a rebuilt at 252K miles only because it started some funky shifting and I was replacing the engine at that point anyway. My WJ is used to deliver newspapers which is similar to taxi service for severity with constant stop&go, U-turns and K-turns. I had to replace the solenoid pack twice in all that time because of the torque converter clutch function.

 

Aamaco tried to sell the PO of my zj a rebuild. He took it in for a fluid and filter chg. When I dropped the pan, the screws for the filter were in the pan and no filter.
And yeah, 80k and 10 years later the 42re still does it's job pretty well. 220k now.