1quick redz28

just recently got my car back up and running with all new front end suspension and k member... the problem i am having is as soon as the car goes into overdrive or lockup i get a chattering and shuddering at any speed or rpm in lockup... when my im just cruising with my foot steady on the gas at 45 to 65 is when it is the harshest. i feel it throughout the center of the car and its pretty bad... ive had it before with the previous motor. trans is a select built race unit with a 3600 lockup stall 10", spohn tunnel mounted tq arm, moser 12bolt rear with a detroit truetrac diff and 3:91 gears.. i believe the driveshaft was shortened and rebalanced and new u joints due to the aftermarket rear... i dont know what to check

any help is appreciated greatly

ArkBird96

Do you have a poly trans mount? They are known for transmitting a lot of vibrations.

1quick redz28

yes and it did it with the stock and 1le mount and stock motor mounts (i have poly motormounts now)