Quote:
Originally Posted by FSETH
T. I bet it isn't that much over 100k.  BMW probably doesn't see any reason to recommend changing the fluid before that mark because they know that the original fluid will last the average trans lifespan anyway. |
And my entire point is that fluid degradation is part of the cascade that leads to transmission failure- that in an internally lubricated mechanical/hydraulic assembly, the fluid
must be considered a wear component.
I do not understand how one can say "The transmission failed at 150k, but it wasn't due to not changing the fluid for 10 years, the parts just wore out"
I wonder if the average lifespan would increase if we had an ATF change at say 40k intervals?
I believe it would increase.
Others here are convinced there is no benefit.
There is no 'right' answer, yet, according to my research. Anecdotes abound, supporting both sides. Plenty of inferences from manufacturers marketing info and 'recommendations', but no public
data from which to draw conclusions. Undeniable historical data supports regular maintenance, but new advances in fluid and transmission design may support extended intervals. Perhaps the discussion is 'how extended'?
A