If you had to add 2L of ATF in the trans and been driving with the trans that low, most likely the friction plates are toast and a rebuild is the only way to fix it. Didn't you notice any oil spot under the X at all?

Unfortunately not upallnight :( My previous tranny failed (before I got more adventurous with trying to fix it myself!). Got a second hand one and had a local mechanic fit it - worked fine for about 2 months, started slipping and then it just gave up :(

Transmission down shift hard
 

Hi,I'm newbie here.I changed transmission fluid on my 2005 BMW X5 E53 3.0i with castro transmax import multi Vehicle which said compatible with BMW.Lately I get trans failsafe pro. come up, downshift was hard and upshift slow ( although drive is fine)I think the fluid was incompatible with my BMW.Can I use Mobil 1 ATF Oil Dexron VI to replace fluid.I want to try before take the car to dealer.
Thanks for your input

The only aftermarket fluid I have "heard" to be acceptable is Redline D4. Be VERY careful as our transmissions are quite picky and will disintegrate for no reason as it is, let alone if we don't give them what they want! :stickpoke

:iagree: IMO no good reason to use anything other than what came in it.

Current ZF rebuild claiming to be from German factory is $2650 here

Europeantransmissions and...

:dunno: :dunno: :dunno:

Their reman process claims are here

remanufacturing process

Mike

The re manufactured trans from ZF gives you a two year warranty and this is the warranty that BMW gives you if you have the dealer do it for you. I would be skeptical of the transmission in the post you provided because 1.) it is not a remanufactured trans from ZF 2.) the warranty is only one year.

Whenever you're talking about an AT on this list, it is probably a good idea to check exactly what type you have and put it in your posting. The ZF's vs. the GM's are pretty different.

I'm pretty sure that your '05 3.0i has a GM AT in there, just like in my '01 3.0i. 5L40-E/GM5 (A5S 390R) to be exact.

BMW's current specification for ATF in these is DEXRON VI. Any ATF that is certified to meet the DEXRON VI spec is good to use. I do not think your Castrol Transmax is certified as such. But Castrol does make a DEXRON VI that should be fine. None of this applies to the ZF AT's; those are different.

If you're still trying to figure out what to do, I would recommend doing a fluid change or two or more with DEXRON VI. You will find some brands that say they are certified to meet the specifications of DEXRON VI, and some that say they work OK in cars that need DEXRON VI. Subtle difference there, so pay attention, and choose accordingly.

For example, Mobil 1 (and Redline, etc.) certainly make high quality fluids, but they may not be DEXRON VI certified. It will be a matter of opinion as to whether you opt for the high $$ non-certified brand vs. the low $$ certified brand. Up to you on that one. But remember it's a General Motors transmission you've got in there. Same as in my neighbor's Cadillac.

Good points.

They appear to be taking advertising license by stating they have a facility in Germany :dunno:

Mike

I used febi. 3k miles later no complaints.