4L80E oil sample after radiator issue with 2010 oil sample.

[WarWagon]

Did I dodge the bullet? 4L80E oil sample after radiator issue.

I have the old sample 2010, ~25K miles ago before a pan drop oil change. The trans was sitting so a lot of oil from the converter had drained into the pan. Sample was before change. Next sample was just taken and has the 1993 4L80E on it to compare.

View attachment 1995_1993_Sample_Results.pdf

2010 sample baseline before oil pan drop oil change/filter replacement.
View attachment 1995_old2010_Sample_Results.pdf

Last time I had a 'drain and flush' oil sample the engine made it 7K miles before failure... :skep:

 

[Will L.]

Drain/flush has been death nail in many a tranny. The detergent in ATF is so god at cleaning that it will clean clutch disks that are "holding on" to letting go. Kind of a common practice among most tranny shops is to tell customers "we believe this will buy you some time that you wouldn't have had, but went it starts slipping..."

I am not a tranny guy but I have ran fleets with many identical trannys. I either religiously change fluid and filter at 30k or never. Working yours as hard - definately change frequently. If the radiator supplier will eat 1/2 the bill I would rebuild it while you can schedule it instead of on the road. That all said ya the numbers look like you should be ok for now. I just push the rebuild for the$ from radiator company.

 

[WarWagon]

Tests show that you change the fluid and then change it again after a few thousand miles so you get the dirt the new fluid picked up out. At least with a neglected unit. Always drop the pan with a flush as there is a layer of 'dirt' in it. Dirt is wear particles of course.