Quote:

also i would check the firing order because cylinders number 5 and 7 are too easy to mix-up. on another note, one cylinder may not be firing. to check it: with the engine running remove the wire from the spark plug and slowly take the wire away from the plug. you should hear it ignite and as you take the wire away the engine will sligthly slow down, if everything is fine with that cylinder. if the engine doesnt slow down, there is something wrong with that cylinder. put the wire back on the plug and repeat for all cylinders. there are special pliers to do this so you dont get shocked from the ignition.

They are easy to mix up, I've done it,but they are correct now.This vibration is not constant, like when there is a bad plug wire. It is harmonic in nature, most noticable at about 45 mph, but also while parked in N or P, once the rpm are brought up to about 2000.Today I removed the poly trans mount and installed a OEM one.Helped alot, but still noticable harmonic vibration around 45mph.I have heard from a couple others who have installed these and have no problems.I had the poly one on my old motor and trans, and same deal, so I removed it and put on OEM one.Is the rubber mount just masking a problem? Again, what baffles me most is that I had the same issue with old motor, trans, torque converter set up.Exactly the same.

Facts are stubborn things.