Clunking after transmission rebuild

[Lead_farmer]

I recently had a transmission shop rebuild my O1E. For this job they dropped the tranny without pulling the engine. Now that it's back together I'm experiencing a fairly violent clunking coming from the underside during 1st 2nd and 3rd shifts. The issue is most noticeable at low speeds and seems to be directly correlated to the throttle.

For example I'm in a parking lot, shift to 2nd, lightly hit the gas- clunk, get up to 25mph, let off the gas- clunk, lightly press the gas- clunk. Much more noticble in 1st much less in 3rd.

Before the transmission repair this was not an issue. Please help me diagnose. Thanks in andvance

One last thing I live 8 hours away from the shop the did the work so if I can I'm going to fix it myself.

[LINDW4LL]

Sounds like a mount issue. Not sure how they'd screw that up but it's worth inspecting.

[christianb5s4]

If they are stock mounts, there's a chance one or more of them tore while trying to get the transmission in and out while keeping the engine in the car. Engine or transmission mounts are the most likely suspects.