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What would cause a vibration in reverse only. When I shift to R with foot on the brake I notice a vibration. doesn't seem to happen at any other time.

Is this just at idle speed? Does it feel like the engine is misfiring?

Could be a bad motor mount?

keeferfish1 wrote:What would cause a vibration in reverse only. When I shift to R with foot on the brake I notice a vibration. doesn't seem to happen at any other time.

Take a look at the path of the heater hoses, power steering hoses, and AC hoses. See if they are touching anything when the engine rocks into it's reverse position that they don't touch when in drive. I'll bet your power steering hoses are touching something on the firewall or that goes to the firewall when the engine moves against the transmission in reverse.

Only at idle.

Drove on the highway for the first time since the engine swap and had the vibration anything over 60-65. I'm not sure I got the mount that goes from the pan to the block all the way on the top pin. I think this might cause vibration. I will take it off tomorrow and adjust, hopefully this will take care of it. On another note the flywheel was slightly bent which wasn't notice until after the install we were able to bend it back a little and it seems fine. I hope I'm not removing it again and the motor mount fixes the issue.

Flexplate (which you referred to as a flywheel) is a finely balanced part. If it is bent out of shape and not back in perfect balance, it could definitely cause a vibration.

I would think the flywheel would cause the vibrations in neutral too, just revving at 2-3k rpm.

Definitely the front motor mount. I put it on the lift last night and found that when we installed the front mount the top of the mount against the engine was not all the way on the pin so it was not tight. I remove the entire bracket except where it bolts to the pan and made sure to jack up the engine until the mount was all the way against the motor before I tightened everything. Problem solved.