01 X5 3.0 Auto Trans

[ronzoni89]

I've been messing with this trans for a month now.... Last fall I did a filter & fluid service, and have since learned I killed it by using the wrong fluid. The last 4 weeks I have torn my knuckles up removing the transmission and transfer case in my shop here in Iowa... Nothing else to do in a long Iowa winter While I was at it I fixed several oil leaks, had the starter remaufactured, the alternator remanufactured, new valve cover gasket, new spark plugs, change oil filter housing gasket, new oil separator system valve/tubes....

All is back together, running very well... but for one thing. When heating up to operating temp, trans will shift with a little flare from 4 to 5, throw the little yellow gear light on the dash, and will just stay there in 4th gear. Stop the truck, try to drive off, still in 4th gear. Turn off engine for 10 seconds, restart, and it has healed itself. Will do this intermittently, but always lights up on the 4-5 shift, and always hangs there in that gear. Always heals itself when engine is turned off and restarted. My code reader will usually give me a "No codes found" message.

Since this seems both temperature related, and also electonically/ self healing, my study of the various laments online here point to the temp sensor in the internal trans wiring harness. BTW, the trans is the A5S390whatever (Can't remember the last letter) It's the French GM unit with the grenn sticker on the pan, Dexron VI. BTW, the Castrol Transmax Import Multivehicle ATF was what killed it.

The rebuild consisted of all the hard parts, clutches, steels, seals, torque converter, and all the electrical stuff in the valve body, all 5 solenoids, except for the internal harness, which has the temp sensor built in. The rebuild was done professionally, I just did the R&R with all of the various other things necessary to do it. The #6 to #10 pin on the electrical connector on the trans is the two that correspond to this temp sensor, book says I should be getting 5600 or so Ohms resistance.... It's hard to tell whether or not I'm on the right two pins, but one set says 20 ohms and the other set is open, neither of the two possible combos gives anything close to the temp sensor ranges given in the book.

[trentmw]

What fluid did you put in that killed it?

[99323is]

BTW, the Castrol Transmax Import Multivehicle ATF was what killed it.

[trentmw]

Doh... Missed that part sorry

[tmv]

GL with figuring thing out, ronzoni89.
For reference, I used Castrol Transmax Dexron VI in my E53 with GM tranny, and Castrol Transmax Import Multi-Vehicle in my E39 with ZF tranny.

[TiAgX5]

Originally Posted by tmv

GL with figuring thing out, ronzoni89.
For reference, I used Castrol Transmax Dexron VI in my E53 with GM tranny, and Castrol Transmax Import Multi-Vehicle in my E39 with ZF tranny.

I did 4 drain/fills at 100k miles with the Castrol Multi-vehicle, new filter installed with the final one. ZF 5HP24 trans with over 160k miles now and operating fine, even with thousands of miles pulling trailers in the 6k to 7.5k lb range. Stop and go construction traffic (Dallas area) pulling a 7500lb trailer in 115 deg F heat with AC on high and the trans has held up.

[ronzoni89]

Turns out there was a potpourri of possible fluids that BMW was using, depending on what they had sitting around available, apparently. My research and experiences with this over the last month conclude: The BMW dealership cannot tell you what fluid to put in your X5 by giving them your specific VIN code, which tells them which transmission was installed in it. They need the actual number off of the sticker on the bottom of the pan, mine happens to be green... Which says to me that they used different fluids in the exact same transmission, and identified that difference on the day it was built with a sticker on the pan, but not traceable back through the BMW build records by VIN code.

Astonishing, especially since any intermixing of the fluid types they were using is BAAAAADDDDD! I equate it to doing a blood transfusion and using the wrong blood type.... All the experiences I see in these forums that indicate transmission failures within 10,000 miles of a trans service suggest that this fluid intermixing is the culprit, not some disloging of sludge in the valve body, etc....

My transmission was supposed to have had Dexron VI, I used the Castrol Transmax Import Multi-Vehicle, and had a transmission failure within 10,000 miles.. CAUTION: Advance Auto database is who told me Transmax Import was the correct stuff... I wish I would have done better research last fall on the sticker color thing, etc....

I'm certain my astonishment is only due to my simplistic American ignorance of the beauty that is German Engineering

[ronzoni89]

TiagX5, the issue isn't that the castrol Import fluid is bad, it's that you have to know which fluid your trans was originally filled with and be certain to use that... My trans was the GM A5S390... , yours was the ZF, a whole 'nuther can of woms decoding the sticker clors on the bottom of the pan that correspond to a specific fluid type it was filled with.

Lesson learned is don't mix the types, EVER.

[electricalserv x5]

I think that's what killed my transmission,F--kin A-----le Indy here in Ardsley told me I had to replace the transmission cooler lines,line borke off,tranny fluid every where. He blamed the parts.
Now I am rebuilding the transmission,$4200 .................
I,ll tell You , You can,t just have any one work on these cars.

[ronzoni89]

I know.... I'm getting to a point where I won't let anyone else work on it for that reason... I just wish that BMW wasn't so secretive about their service/repair information, I get it they want to hold their owners hostage for these services, but it's seriously driving me away from ever buying another one. Ive got a 97' Jeep Grand Cherokee with 220,000 miles on it that has had WAY less $$$ spent on repairs, and it's WAAAAYYYYYY easier to work on! But there, were back to the simplicity of us American ignorant savages...