So last time out at the track. We went to leave on the 150 shot and we broke the rear right off the bat and it nailed the rev limter and I shut it down.

Well we get the new rear in and go to test it out. I put it in D and the motor just freewheels. I pull it into 1st and it will move and then shift it to 2nd and it shifts but no shift into 3rd at all.

There is no speed sensors in the rear anymore and the harness is not connected.

WE are pretty sure we blew up the sun disk and planataries but just wanted to make sure that it sounds like we broke the tranny rather than some comp. electrical isssue.

Also when on jackstand it will move in third and act normal but once on ground it doesnt do anything. same thing with OD.

this is a stock 4l60.

 

Its very common to break the low roller clutch during a rear end failure . And possibly more

 

ok what we were thinking is when the rearend broke it nailed the rev limter shifted into second then into 3rd before i had a chance to react then the rear caught the good teeth and yanked the rpms back down in 3rd resulting in bang bang. lol

 

also what would cause 1st and 2nd to work when manually selected but not when put in D or OD? just a weird situation

 

No because the low roler clutch is bypassed by the low/reverse clutch in low 1 and not used in 2nd

 

It is not uncommon at all to see a mechanical failure in a transmission after a rear axle lets go on a hard hit. Usually the low roller and input sprag take the abuse. I have seen planetary gear sets grenade as well.

You definitely have an internal hard parts failure. Unfortunately the unit will need to come out for repairs.

Good Luck, give me a shout if we can help.

g

 

thanks guys I really appreciate it. About to go take it out of the car right now and see whats up with it. Ill try to update and let you know what failed.