I got my transmission partially rebuilt last week, meaning I got a rebuilt torque converter, new clutches, gaskets, and all the soft parts like that. The transmission seems to be working fine, but when I hit the gas pedal and the engine is under a certain amount of load, somewhere between 1000 and 2000 rpms, i get a squeel, or squeek, or beep sound, in every gear including reverse. It lasts for a few seconds until I get a little higher in the rpms. I took the truck back and they thought it might be a vacuum issue, but I don't think they found anything. I brought the truck home as they were closing for the weekend, but I am taking it back over there next week so they can try to figure out what the noise is. Anybody have any insight on this? Thx.

 

Sounds like belt slippage, get a goodyear gatorback and be done with it.
Alan