I got my converter installed the other day and everything is fine exept when im easy on the gas and it shifts into over drive at say 45mph and if i have my foot on the gas it will make a grinding sound.. that sounds like a bad u-joint.. It doesnt do it at any other time. I can get it up to 50 real quick and let off and it will shift to OD with no grinding sound.. it only happens when i have my foot in the gas? Is it a bad u-joint?

 

It might be your converter slipping mine did the same around the 3 to 4 under load at low rpms a tune will fix it I dont think its anything to worry too much about

 

hopefully they filled the TC with ATF before they put it in.

doesn't sound like u-joints to me

 

sounds like something is happening while the converter is locking-up.