FIREGRV8

I have a 94 formula that i got and put in an rebuilt corvette spec LT-1 and rebuilt the 4L60E. After all the rebuilt and install was done we drove the car and for the first day so far so good. The second day we took it out for a 50 mile drive and when we were almost back home when the car all of a sudden started to downshift and eventually stayed in first gear and limped home. The car goes into gear and after a couple of minutes when it gets warm the same deal. Also when you start the car there is a weird humming sound. We opened it up found the filter cloged and cleaned all the cooler lines and transmission guy changed the 4th gear clutches that got burned (new rebuilt kit!!!) He also checked the valve body and put it back together.
Same thing happened again within the same timeframes. The transmission guy says that it may be the converter, others say it may be the pump, both were replaced with rebuilt units. Any ideas I don't want to get any further in my pockets before I have a slight idea. Any input greatly appreciated and very valuable

z99ls1

iTrader: (12)

sounds like your tranny fluid might be getting hot and putting the transmission in "limp mode"? Do you know if your tranny is locking up? If not it could be slipping the whole time and cause your fluid to get hot and send the transmission to limp mode. See if your trasmission fluid is dark or if it smells burnt. If it gets to hott it can burn your clutches. This is why the car is probably not alowing you to shift into the other gears..