Originally Posted by MolaKule
Originally Posted by kstanf150
...They were all maintained according to the lifetime factory schedule
None of em towed anything but grocery's and their butt up and down the road
So
Sir I respect your knowledge but you and I will have to agree to disagree on this topic
On my end I don't see transmissions being any better than they've ever been and thin life time fluid is not helping and only gona make the dealers a lot of money down the road
But you haven't proven that thinner ATF's were the cause, which was your original hypotheses.
I know for a fact that while ATF viscosities have been lowered, the additive packages, which contains improved AW chemistry's, are 10 times more stable and robust than previous fluids. I have not seen any SAE or rebuilder data that links lower viscosities with increased failure rates. Add to that better base oils and you have much improved fluids over the old Dex/Merc fluids.
I can relate one situation where certain GM transmissions in light vans and SUV's (I don't recall the exact GM designation) failed almost on target at 100k. But the transmission rebuilder I worked with, and which my daughter was the parts buyer, found it was the transmission's design, or lack thereof, that was the primary cause of failure, mostly due to undersized parts, poor metal treating of splined shafts, and poor shift timing.
The fluids of these failed of transmissions were analyzed and the fluids themselves were found to be in good shape, so it was not the fluid that caused the failure, but the internal design of this specific transmission.
Sir you are correct
I shouldn't have assumed that the transmission failures I've been associated with was failure due to fluid. So I apologize for assuming, as you've stated the failure Is most likely due to either design/part failure or just bad luck.