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Old 01-27-2013, 09:27 AM
schpenxel schpenxel is offline
Location: Greensboro, NC
Join Date: Nov 2009
Posts: 3,438
Mein Auto: 2004 545i
Originally Posted by Vapiano View Post
Hey Guys,

Today for the first time I felt what everyone else has been talking about, around 34-40 mph the car seems like it doesn't know what gear to be in 4th or 5th. It gently switches back and forth between the two until I get to about 42 mph or step on the accelerator a bit harder then it goes away. There is also a slight delay when I put the car in reverse before it begins to move. The car has 60k miles on it; this allowed me to purchase a B2B New Car warranty from my credit union when I purchased the car this past December. It covers everything as if the car was new and seals are included!!!

I put the car up on a lift and saw no leaks at all coming from the tranny. I am dropping the car off this week to an Indy to get it checked out. Based on what I have read; it appears to be the valve body seal needs to be replaced. Is this the same as the mechatronics sleeve?

Also, for you guys that are doing this job yourself, how in the hell are you getting the oil back into the tranny?
I would recommend you try to get them to just replace the whole mechatronics assembly with at least a rebuilt one from ZF (via unless they're willing to just replace the whole transmission--that would be even better!! No, the mechatronics sleeve and valve body seals are not the same. If you did not see any fluid leaking, then the mechatronics sleeve is fine, although I would have it replaced as well if at all possible while they're working on it. It's relatively cheap and known to fail.

There are a couple of different terms people use regarding seals on these transmissions that are hard to distinguish between. The "mechatronics seal" is what people usually refer to the seal between the electronic connector between the mechatronics unit and the plug from the car. It is #2 in the drawing below. It is accessible and it is common before it to begin leaking. It basically keeps the oil in the transmission but lets the electrical connectors out.

As far as the "valve body" seal, that could be many different things, although technically I would think it is one of the seals actually inside the valve body. I have read about these transmission extensively and would recommend just replacing the whole mechatronics assembly if possible unless you have a transmission shop that really knows what they're doing on these. There are shops that will rebuild the valve body portion for under $1K, but since you're under warranty, hopefully they'll go the "easy" way and just replace it.

How much longer do you have on the warranty? It sounds like you have a while, so at least you won't be bad off if they put a patch on it this time then it fails again later and they have to change some expensive parts.

As far as getting fluid in, it depends on which model you have for the specifics, but on mine there was a plug on the passengers side of the transmission. I had to buy a hand pump and snake a hose up into that fill hole. You first fill it up until it overflows with the car off, then start the car and let it get to I believe it was 104* and add more until it overflows again. Yes, being under the car, right beside the hot exhaust pipes is not a very joyful experience. Once the fluid is slowly dribbling out and the temperature is in the recommended range (104 to 120 I believe it was), then you put the bolt back in and you're done

Also, for the record, I doubt that picture is of your actual transmission. It was just the first one I found googling that showed something similar, so don't take the picture too literally as far as how the layout goes

Last edited by schpenxel; 01-27-2013 at 09:32 AM.
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