No i asm not running a snumber and i have poly motor mounts.I am going to put a new tail shaft on it tomarrow and remeasure to make sure my drive shaft is not to long. is there a way to measure the out put shaft for straightness with out taking the trans out of the car? If not so be it i might just pull the trans.also at 125 mph in the 1/4 the car was smooth. i mean no vibration that i could tell or fill. could the drive shaft be bent enough not to fill it under power but enough to do what it did. the machine shop that change the rear joint to the 1350 said the drive shaft tested out fine.I think i am going to get a new poly trans mount for the car.i will put it back togeather and will let every one know how it does.thanks mopar65