Hi guys,

hope someone can help me out with some tips here.

A few days ago after I did a run on the dyno a bad vibration developed.
I checked the U-Joints and clamps, but they look fine and have no play.
Wheels and tires are new and balanced not long ago.

I don't know what else it could be.
As I live in Belgium it is not easy to have a shop look at this as they have not got a clue about Chevelle's.

Any help woild be very apreciated.:hurray:

Oliver

We need a little more information to help you. Does it vibrate if you race the engine up in park or neutral? Or only when driving it down the road. You could have a locked up U-joint, and it will feel tight, the correct way to check your u-joints, is to remove the driveshaft, and physically move the joints, and feel for any tight spots in either direction. Also, depending on which u-joints your car carries, make sure that the rear joint is centered in the rear yoke. The early Chevelles have a small tit on each side of the rear yoke to center it. The next size up joint uses "C" clips installed on the u-joint caps to center the joint in the rear yoke. It is very common for people, (not knowing any better)to leave these clips off, and it will vibrate bad.

you may have thrown a wheel weight.

We need a little more information to help you. Does it vibrate if you race the engine up in park or neutral? Or only when driving it down the road. You could have a locked up U-joint, and it will feel tight, the correct way to check your u-joints, is to remove the driveshaft, and physically move the joints, and feel for any tight spots in either direction. Also, depending on which u-joints your car carries, make sure that the rear joint is centered in the rear yoke. The early Chevelles have a small tit on each side of the rear yoke to center it. The next size up joint uses "C" clips installed on the u-joint caps to center the joint in the rear yoke. It is very common for people, (not knowing any better)to leave these clips off, and it will vibrate bad.
The vibration starts at about 50 - 60 Mph and gets worse the more revs the engine makes.
The U-Joints were all replaced about 1000 Mles ago and come with clips.
The car is a 1970 Chevelle with a 12 bolt rear and a TH 350 and a 350 motor.

Thanks

Oliver

you may have thrown a wheel weight.
I checked the wheels and they seem fine.

Just because the u joints are new that dont mean they are good, also i just had to purchase a new yoke for my 70 chevelle and the driveline shop i purchased it through said that if your going to replace your u joints you really need to have the driveline balanced and also he told me that when replacing u joints make sure that the yoke goes back on exactly the same way as it came off, in other words dont turn it 180 degrees and then reinstall or it would certainly be out of balance. Dont know how true or false this info is but the guy has been in the business for quite sometime and has a good reputation

Just because the u joints are new that dont mean they are good, also i just had to purchase a new yoke for my 70 chevelle and the driveline shop i purchased it through said that if your going to replace your u joints you really need to have the driveline balanced and also he told me that when replacing u joints make sure that the yoke goes back on exactly the same way as it came off, in other words dont turn it 180 degrees and then reinstall or it would certainly be out of balance. Dont know how true or false this info is but the guy has been in the business for quite sometime and has a good reputation
The problem is that there are no diveline shops here in Belgium.
So I need to do it al myself, hopefully with the help of you guys.