To flush or not to flush
 

My '08 e70 is approaching 100k miles (75k of which are mine). It doesn't get driven too hard, no hauling, etc.

Wondering if there is more risk than reward in flushing the transmission fluid and replacing with clean. I've seen multiple notes on BF saying not to touch it because you'll release all the goop and possibly damage the transmission, and others saying "if it's a power flush, you should be fine". The x5 is acting fine, but wondering all the same.

I have a 2008 x5 4.8i at 88k miles, and I am going to change the oil and filter soon, I think it is better because you are getting rid of all the gonk in the pan and filter and replacing most of the oil in there with fresh oil, i did it on my last BMW and it worked better, but that is my experience, after all most transmission lifttime oil means 100k mile.

It can go either way,there is a risk involved.It is not unheard of shifting problems after fluid change.I would say less likely under 60-70 k miles and more likely after 100 k miles.

Shifting problems can be caused by not performing the process correctly or using the wrong or different oil, I always go with the recommended oil from the manufacture, it is way more expensive but cheaper than a new transmission.


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Absolutely agree for the oil.However,the transmission valve body is a very sensitive hydraulic device with countless small orifices.Once the system is "shaken" by the oil and filter change and some air bubbles going thru the system on the initial start-up after the new fluid is in may cause one or few microscopic objects to get into the VB and affect the way the fluid is flowing thru the servos and accumulators.The older the tranny,bigger chance for that to happen.

I am in the same boat with my X5, just about to hit 160km and I am doing mine.

I really think the oil change problems is more of a myth than fact.

100k is safe to do, I hear problems with people doing a flush and "freeing up" crud and it causing a blockage but personally have never seen it. And if that does happen it was going to eventually happen anyway. You more than safe at 100k that's a good time to do one. Normally I do a flush and put 3k on it flush again and change filter but that's just me

+1

I think you meant NOT a power flush.

CRAVIN

If you've seen the arguments both pro and con regarding the issue then you
know additional opinions should not determine your decision. Just decide
and live with the results.