[Tom]

I recently started having an issue with my 1998 pickup. The trans was rebuilt about 1/5yrs ago. When built, I went with my own supplied torque convertor. I have been unhappy with it since install, as I can tell it wasn't balanced correctly. I'm now assuming they also rebuilt the lockup clutch badly as well based on my issue...

I will randomly get what I believe is a torque convertor shudder on the freeway, followed by the TC unlocking for a mile or two before locking back up. I haven't felt the problem on side streets. Its random and not often at all, except for one long on ramp I take twice a week. After climbing up that 1/2mile uphill ramp it will shudder and unlock the TC when I reach 4th gear every time. The shuddering followed by unlocking for a bit before going back to normal makes me think the TC clutch is slipping with a heavy load and the truck is noticing and unlocking for safety?