Quote:
Originally Posted by XMetal
///M cars have a much tighter tolerances and people tend to drive them more "spiritedly"  Therefore requires trans and diff fluids changes every inspection 2 (approx. 50k miles depending on how you drive). Some change them on every inspections. My ///Mcoupe's trans and diff fluids looked clear when I last changed them out at 23k miles (inspection 1).
Non-M cars supposedly have "lifetime" fluids, but I would change them out every 50k miles or so, if it was my car. If you use the right fluids and complete you change procedure properly, there should NOT be any issues for swapping out the fluids. People reported issues either:
1. Used the wrong fluids
2. Improper refill procedures
3. There's probably something already wrong that prompted them to change out the fluids in the first place.
FWIW, I've changed out the "lifetime" fluids (transmission, both diffs, and transfer case) on my X5 at approximately 50k miles and everything is still running like a top now at 88k (knock on woods). All the fluids that came out were very dark, but didn't look/smell bad, but it's always great to have fresh fluids.
Bottom line, don't skimp/cheap out on fluids. Just pay up for the correct fluids and do it properly if you're going to go through the trouble of changing them. |
Totally agree with everything said above. Good upkeep is usually cheap insurance that everything will work correctly in the future. Im not sure about the older model years, but i know that on the 06-08 models the fluids are "lifetime" in regards to diff and trans. Whatever that means. I would assume that unless you are doing heavy duty track sessions regularly i would change the fluid every 50k miles on the z4.
I believe on mine im going to change every 30,000 as that is what i just hit. Furthermore, for M The schedule says to change diff and trans fluid every inspection II.