Quote:
Originally Posted by Kirra
Hey there, I could use an expert opinion to see if I'm on the right track for troubleshooting the automatic transmission issues on my 2002 4.4.
It has 183k with unknown transmission service history. I traded an E46 wagon for it 2 weeks ago.
-Shifts normal in 'D' until it's warmed up.
-Has never given an error code.
-Issues go away (or more likely just masked) when in 'S' or manual. Haven't tested this on long drives though.
-When warm, it'll shudder between 2nd and 3rd, particularly under light throttle and going uphill.
-When warm, it'll hunt in 5th gear. It acts like slipping, but doesn't seem to be affected by throttle.
-When hot, after driving for a very long time, it'll hard downshift into 1st.
My thought process so far...
-It's temperature related, and issues get worse the longer (hotter) it's run.
-I *think* being that the issues are in multiple gears, I could rule out anything related to a single gear.
-The temperature sensor is easily diagnosed ( https://xoutpost.com/986442-post13.html)
-If the temperature sensor checks out OK, what is the proper temperature for this trans to run at, and how do I read it while driving?
-Following the last bullet, if I find it's running too hot, are the trans cooler and thermostat the only culprits?
Let me know if you think I'm on the right track, and any assistance you can lend on the questions above. What I don't intend to do is throw parts/time/money at it without proper diagnosis.
Thanks! |
Not going to find that "Expert Opinion" on this board. Don't know of any members on this board that rebuild ZF trans for a living. There are people who have rebuilt their ZF trans on this board and posted their experience.
If you looking for an "Expert Opinion" you should look at "Gary Ferraro's" Youtube channel. Gary has placed on his youtube everything you wanted to know about disassembly and rebuilding the ZF trans in X5, Jaguar, and Rover.
You have a hydraulic pressure issue that is related to the ATF temperature. The clutch packs that engage the gears are not able to maintain pressure because of the hydraulic pressure issue that is why you have the shudder and the slipping. The hard shift from 2 to 1 is because of the pressure valve in the valve body. The pressure valve is a known problem with this trans.
Two weeks after acquiring the X is why the previous owner was willing to trade this X for your E46. He already knew about this problem and was just looking to dump the X.
The only part that will fix this problem is a new or rebuilt trans. You can always listen to the Cliff Clavens on this forum and try a fluid change, or a new harness with a new temp sensor, or a new or rebuilt valve body or some new solenoids, but in the end, all those suggestions are just WAG (Wild Ass Guess).
Flame on I got my fireproof suit on today.