Originally Posted By: friendly_jacek
I thought it was well established that neglected/weak trannies tend to fail after flush when there is a rapid change in fluid quality?
Not a fact in the sense that it's the new fluid that "kills" it. The common scenario is this (which comes from a host of people that design and build trannys as well as those that repair them that I have interviewed over the years):
-The tranny is essentially dead at the beginning of this already and the burned liquid within it has lost all or most of it's lubrication qualities, certainly the friction modifiers (FM) that make for smooth shift.
-More often than not, there are adverse symptoms, mild to severe. The owner, often feeling guilty for the neglect, or having thoughts about the future major expense, is desperately hoping some easy fix, like an oil change or "tranny-overhaul-in-a-can," is going to fix it.
-Fresh oil is installed. It's robust with FM and lubricant qualities. Unfortunately, the only thing that was making those poor, worn, abused clutches grab each other is the lack of such lubrication qualities, so they almost immediately begin to slip. Slippage destroys what little clutch material is left and throws even more junk out to circulate thru the trans. It soon dies altogether.
-A variation, or a second aspect, of a sudden failure of this nature is that all the buildup of failure debris and collected contamination that, once the new oil is installed, has been collecting in a neglected, abused or failing trans is broken loose from the corners where it's been hiding and causes failure this way. When the oil is "used up" all it's detergent and anti oxidant capabilities are used up as well. The new oil has all these qualities so it starts to clean up the trans... with disastrous results.
There are variations of this, of course, these being the most common scenarios. But take this to the bank: (the correct) new oil will NOT hurt a good tranny.
Also, you have to go pretty far from the required fluid spec to induce a short term failure in an automatic trans so I sincerely doubt the MaxLife was the cause of this. Where is Whitewolf when you need him! Oil Changer, I know your wallet and pride are stinging from this but your attitude is pretty irrational.... understandable.... but still irrational. But, this forum gives you a chance to vent a bit. Call it BITOG therapy ( : < )