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525e34
04-22-2005, 10:10 AM
My "new" 1995 525i has 98k miles and unsure when/if the PO last changed the auto tranny fluid. No problems with performance ( GM A4S 310R ) - just bothers me not knowing. Here is my "cautious" ( anal ) approach in case the fluid has never been changed:

1) Drain pan only and refill with Mobil 1 Synthetic
2) Drive approx 500 miles
3) Drop pan & sump, replace fluid, new filter, gaskets and Mobil 1

The thinking is the first change should allow the Mobil 1 to clean out/loosen crud, the second get it out of the transmission. This seems to be the common theme in previous posts. Any other thoughts?

Also -is there a crush ring on the drain bolt? Can't find any listed on parts websites and my filter service kit doesn't have one.

ryan roopnarine
04-22-2005, 10:26 AM
i've been trying to get a straight answer out of people in the know about this for a long time.....I SUSPECT that mobil 1 atf might clean, but that might be harmful to the smaller passages in a transmission valve body, as opposed to a engine and its comparitively larger passages. i'd say that it probably DOESN"T clean.

632 Regal
04-22-2005, 10:31 AM
dont that trans take dextron III? if so any synthetic dextron III is good.
Rule of thumb on higher mileage transmissions is drain fluid and change filter, refill and dont change it for at least an additional 20k miles. Theory is if you "shock" it with flush after flush of new stuff it wont be happy anymore.

Russell
04-22-2005, 11:37 AM
Recently I had my indy put in amost 7 quarts (empty about 8.8 quarts) of Mobil 1 synthetic atf with a new filter kit. They drained and cleaned both pans and blew air through the oil cooler lines to remove as much of the old fluid as possible. They left the old atf in the torque converter as there is no drain. Note, they did not flush, they drained.

BTW, the trany had been fully serviced with filter etc. about 31,000 miles ago. While I did not notice a problem before the change, It seems as if the trany now shifts slightly smoother and has a littlle bit more pep off the line.
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My "new" 1995 525i has 98k miles and unsure when/if the PO last changed the auto tranny fluid. No problems with performance ( GM A4S 310R ) - just bothers me not knowing. Here is my "cautious" ( anal ) approach in case the fluid has never been changed:

1) Drain pan only and refill with Mobil 1 Synthetic
2) Drive approx 500 miles
3) Drop pan & sump, replace fluid, new filter, gaskets and Mobil 1

The thinking is the first change should allow the Mobil 1 to clean out/loosen crud, the second get it out of the transmission. This seems to be the common theme in previous posts. Any other thoughts?

Also -is there a crush ring on the drain bolt? Can't find any listed on parts websites and my filter service kit doesn't have one.

632 Regal
04-22-2005, 11:48 AM
once its changed a couple times you can change it more often

RickyJ
04-22-2005, 11:54 AM
I've changed to Redline ATF in the same tranny as yours and changed it twice. I got out 8.5q which is double other's experience. I'm not sure why, but the car stood overnight with the pans off, and tilted slightly forward on the jackstands.

Beachcomber
04-22-2005, 03:11 PM
Here's my post from last year. (http://www.bimmer.info/forum/showthread.php?p=20852)
Still running strong!

525e34
04-22-2005, 03:16 PM
Thanks a lot for the info. How many miles did you drive between each oil change before you dropped the pan and filter? Also - does your drain bolt have a crush washer?

Beachcomber
04-22-2005, 04:02 PM
Thanks a lot for the info. How many miles did you drive between each oil change before you dropped the pan and filter? Also - does your drain bolt have a crush washer?

I drove at most 5 miles total between drain/refills - I just hopped on the freeway. I ordered a filter kit from Kirt Koeller - I don't recall whether the drain and fill plugs required washers or not....

Beachcomber
04-22-2005, 04:12 PM
Thanks a lot for the info. How many miles did you drive between each oil change before you dropped the pan and filter? Also - does your drain bolt have a crush washer?

Not your transmission, but a good write-up:
http://www.e38.org/zf-5hp30-service.html