What would have caused this?
Pump bushing installed wrong? Converter issue?
It's not rocket science.
Something out of alignment, run-out, grounding issues, clogged cooler, etc.
Is it true? You have two sizes on a 4l80e on pump bushings, (thickness). A 3/8" ground from the block to the frame helps electrolysis from occurring... Hnece the bits and pieces from bunching up and causing failure like you have... Just some experiences....
A little more info on everything. In 2014 I sold the car with a stock 80E (minus HD-2), single disk circle-d, and a stock PCM in the car. The person I sold it to had the trans rebuilt with some better parts and sent the converter back to Circle-D to be upgraded to a multi disk.
I bought the car back a little over a year ago and ran it at the track a couple of times before winter hit. Last year I installed a MS3-Pro system in the car and did away with the stock PCM. I ran the car all year and put a few thousand miles on it without issue. The last race I attended I made 3 passes and noticed a pretty heavy trans fluid smell after my last pass. When I took it off the trailer the next day it was spewing fluid out pretty good so I parked it and haven't driven it since.
Thinking back on this last year, I did notice a trans fluid smell on occasion after a pass and a few times the trans got well over 200* for some reason. It would cool back down pretty quickly so I didn't think anything of it and driving it on the street it never got over 190* no matter what I did.
With that being said, I obviously don't know if something was hurt or not installed right (by the trans shop) when I bought the car back, or if it was a grounding issue when I changed over to MS3-Pro, or anything else that may have caused it. The cooler setup remained the same, the flexplate remained the same, all the grounds were the same, etc.
I am going to assume that I will need a new pump though? Would it be a good idea to have the trans completely torn down and looked at as well?
Thanks all.







