I bought my car knowing the transmission was busted. The previous owner had it rebuilt and then the 3-4 clutches let go on him, thats where my ownership of the car began. So I take it to a different shop and have them rebuild it. 3,000 miles and 1 trip to the drag strip later, i find that my 3-4 clutchs are toast. The torque converter had been locking and unlocking while in overdrive (engine rpm jumped around about ~300rpm whiel in 4th) this was the first sign something was up, so i check the fluid and it is a quart low. I fill it up and the problem goes away, a week later the transmission starts to slip in 3rd gear, it it an intermitent problem, it would shift finefor mile or two and then start slipping again in 3rd . So was the low oil the cause of this or was it somthing to do with the rebuild?

 

A quart low on a 4l60e is substantial and it is possible when you were at the track of if it was pulling air a little causing low line that you may have damaged the 3-4 clutch pack. Since it went away after you put fluid in it this is probably the case. Sorry but it looks like you will be going back into it,

 

You're probably looking at another rebuild. Many "generic" (and some 4L60E specialists) still don't have a clue what these transmissions need to survive. If you're interested in having it built by the best, just click on the link below. We have the best reputation and prices of anyone else out there.
Your 3-4 problems probably started with the converter unlocking. the 3-4 clutches need lock-up to live.
If you have any questions, feel free to give me a call. 302-250-1202

Thank You,
Frank
CPT

 

frank knows his stuff...get your tranny by him and it wil lbe your last...

 

The 4l60's are notorious for dropping clutch packs. I lost 2 just last summer until we finally got a set-up figured out that will hold them and mainly the tranny together. Nitrous was not my trannys best friend.