As you step on the gas and transmission downshifts , the shaking goes away ! Is this a torque converter about to blow and or an ailing flywheel situation ?
When the truck is in OD and under load , truck shakes horrendously ... on 1990 Chevrolet 1500 Pickup
Yes, it could be a slipping/chattering torque converter clutch. A cracked flywheel or flex-plate in an auto trans, would typically be felt in all gears and would tend to make a knocking sounds when the engine is idling.
Thank you so much for that answer ! It is what a mechanic friend of mine diagnosed about a year ago ! So if I replaced the flywheel and torque converter , I'll be in good shape then !!! Thanks once again !!!