early vs late 4l80e
The person im buying the trans from has offered both early and late years to me so im looking for some input on what i should go with. Ive heard the 99+ had numerous updates, but ive also heard rear planet failures are more common. This is going to be a stock trans for now, but im seeing that valvebody and converter later on should take care of me when i do get the turbo on.
Thanks for the help.
The Lube circuit changes were made for the '97 year model.
I cant recall anything major in '99 besides the LS cases with the top bolt hole.
The later/Lower mileage unit is the one you want, 4L80E's are stout units but they do wear out pulling loaded trailers for 100,000+ miles.
As far as the OD roller clutch.....Don't drag race in D4, Put it in D3, The Overruns come on & will protect the OD roller clutch shock/failure.
Rear Planets failing isn't a concern on TH400/4L80E's.




