CleanIsFast Journal: BMW X5 4.6iS

[CleanIsFast]

Originally Posted by smokeyyank

I'll be interested to hear how that works out for you. Mine has a harsh down shift too and I need to get this done here soon.

Okay so I was able to take the X for a long enough drive to get everything up to normal operating temps. New fluid and filter definitely helped. You can still "feel" the downshift but it's definitely not as harsh as it was before. I'll see what the wife thinks because she drives the vehicle daily currently around town.

Note: To my knowledge, old transmission fluid was ORIGINAL. Had never been serviced before. Upon inspection of the little magnetic on the oil pan, there was NO debris, metal flakes, etc. Filled with fresh ZF specific fluid, cleared adaptations, ran through all the gears (P,R,D,1,2,3,4,5), driven around the block. Back on the lift and topped off.

Next up: I have a small vaccuum leak somewhere. I may swap a MAF from my M5 (since I run Alpha N and it doesn't use the MAFs), and see if that helps. I think I have some CRC MAF cleaner laying around somewhere. The previous owner had an oiled intake filter that I threw away because it was gunked up and never serviced. If not, i'll have to do a smoke test. Even though we did one a few weeks ago and it yielded nothing. Could be fuel related?

[smokeyyank]

Originally Posted by CleanIsFast

Okay so I was able to take the X for a long enough drive to get everything up to normal operating temps. New fluid and filter definitely helped. You can still "feel" the downshift but it's definitely not as harsh as it was before. I'll see what the wife thinks because she drives the vehicle daily currently around town.

Note: To my knowledge, old transmission fluid was ORIGINAL. Had never been serviced before. Upon inspection of the little magnetic on the oil pan, there was NO debris, metal flakes, etc. Filled with fresh ZF specific fluid, cleared adaptations, ran through all the gears (P,R,D,1,2,3,4,5), driven around the block. Back on the lift and topped off.

Next up: I have a small vaccuum leak somewhere. I may swap a MAF from my M5 (since I run Alpha N and it doesn't use the MAFs), and see if that helps. I think I have some CRC MAF cleaner laying around somewhere. The previous owner had an oiled intake filter that I threw away because it was gunked up and never serviced. If not, i'll have to do a smoke test. Even though we did one a few weeks ago and it yielded nothing. Could be fuel related?

Good to know, glad it helped out. Hopefully here in a few weeks I can get this hammered out. Need to work on the wife's car first.