The car is a 93 Formy , new brakes new tires. has a bad vibration ..Not really noticeable until like 70 mph...what do u guys think..I was thinking driveshaft....any help would be great

 

Yep, the driveshaft is a very common problem on these cars, your symptoms sound like it. There are a few reasonable options, including the GM 1LE or LS1 driveshafts to replace it. Getting yours balanced may or may not help, but it's a cheaper option. Cheapest yet is to rotate the driveshaft 90 degrees in the yoke which is worth a shot.

Dave

 

lingenfelter has 3.5" alum driveshafts on sale for 299

 

cool guys thanks for the help...I got a shop that will make me one balanced and all for 150... thanks for the help

 

if you feel it in the steering wheel, could be the balancing of the wheels

 

Check out your u joints first. I know that I had a very bad vibration and it turned out to be my u joints were bad.

 

My vibrations start at 80mph... So i switched to a LS1 driveshaft, and the vibrations didnt change at all... I noticed the Rear ujoint on the LS1 driveshaft is pretty stiff, is that normal?

Vibration is underneath the console and sounds pretty violent

 

I get bad vibration under the console as well, I still have the stock driveshaft, All I know is that it makes alot of noise.

 

Mine still has a little bit of the vibration, and it feels like it is coming from below the consoul. That is right were the tail shaft of the transmissoin is. This makes me wonder if the tail shaft bushing on my A4 is worn out and has too much play in it. Just might be something else to look at. I think that the bushing itself is only about $7 at gm, I have just been to busy to take care of it.