Vibration

[Steel Warrior]

I bought a 1934 street rod. While driving I have a vibration. This is what I have done so far balanced drive shaft, changed flywheel, checked wheel bearings, checked rear, rblt trans,rblt engine. The only thing I have noticed is that they used old style motor mounts( the flat style with a donut rubber). They are bolted straight through with a bolt. The bolt is torque as tight has they could get it. It looks as though the rubber is doing nothing. The motor can't move. Should I loosen the bolts a little?Could this be causing the vibration? Thanks your help would be greatly appreciated.

[Matt167]

Universal joint giving up?

[Steel Warrior]

No the u-joints are new also. Thanks

[devil wrench]

does it vibrate when you're sitting still, all the time, certain speeds, certain rpm range? need more info!

[Don Meyer]

Check the angle of the motor & pinion. They should be the same i.e. motor 3 degree down & pinion 3 degree up. Also ckeck the fore & aft alignment of the motor/trans w/the the rear end.
Don

[Steel Warrior]

OK, I will check the degree of the motor and rear. If I can find someone with the tool. There is no vibration sitting still it seems to pick up from 45 mph up and around 65 it feels really bad. Not a wobble just a vibration like the rear is going as fast as it can. The car is taching about 2000-2100 at 60 mph. The rear is a Ford 8" with 3.00 marked on the tag. I figured I was getting the vibration from the mounts on the motor being bolted almost solid. I don't know it's driving me crazy. Thanks for all the ideas!! Might be one of them...

[Steel Warrior]

OH, and yes it vibrates when you step on the gas and not when you let off. Thanks

[lt1s10]

dont forget about the tires. they will bump around that speed.

[Steel Warrior]

Thanks, I will drop the shaft and replace both just to make sure. I did notice a little clunk in reverse sometimes.Thats a cheap fix. I'll double check the tire balance also. Hope it works. Thanks everyone!!

[Ives Bradley]

I would at least loosen up those mount bolts. But thats just me.

[Steel Warrior]

I think I will loosen the mount bolts a little also. Thanks!!

[Steel Warrior]

I want to really thank everyone for their responses. Found the problem. Just like you said. The new u-joints were bad. Just had them checked when I balanced the drive shaft and was told they were OK. Well, guess what someone goofed. Thanks very much!