Hello all,

I tried seraching couldnt get naswer to this perticular question....

I am approaching 50k. Transmission says it has a lifetime fluid in it.

Not sure about is the rear diff fluid is life time.

Questions -
Should I change? What are you people doing? I dont drive car that hard and its just for my daily commute.

thanks

 

I tend to keep cars for a long time, so I don't buy the lifetime story.
Most people lease today for 3 yrs - which makes it easy to manufacturers to market cars as "maintenance free" and "lifetime fluid".

Every car I've owned, I've changed transmission fluid at 70K miles and differential at 100K.
50K seems a little soon.

 

According my BMW certified mechanic by "lifetime" BMW usually means 100K miles. He changed transmission oil when he replaced gasket of transmission cover at ~90k - it was leaking after at least 3 days of not driving and he did not find anything wrong but replaced gasket and leak disappeared, so I should be good for another 100k

 

Well before Synthetics and the BMW maintenance schedule there was VERY VERY different standards for maintenance for all BMW's. I believe that synthetics are far more superior than mineral based products and you can get more miles out of them but I do not agree with BMW. I have build a few engines, diffs and trans in my life(ford only) and did my fair share of 1/4 racing. If you look back at the of maintenance schedule before the "included maintenance", you will see a very different point of view.

exp: e34(89-96) 5series
oil 3k
Trans 30k
diff 30k

Myself I do
oil: 7k (aka pay for every other change)
Trans: 45K BEWARE.. if you have them drop the pan(not the trans flush) you will have to pay for a new pan... it is made of plastic and IT WILL BREAK getting it off. I guess AU is not cost or weight effective... hahah
Diff: 45K


Believe me Synthetics are much better and I have no issues with these intervals...... Why does the BMW diff and trans have lifetime oil....... because the care is only warrantied till 100K... interesting.





My self... Here is what I do..... 7k oil changes, 30-40k Trans and

 

My US$0.02: I'd do the trans fluid at 50K, and the diff oil every 25K.

There is no such thing as "lifetime fills". Well, there is I suppose... if your trans dies at 100K miles because you didn't change the fluid, then the fluid was a "lifetime fill" - it lasted right up until the point the trans died.