My friends car has a real bad vibration above 2500 rpms and gets even worse the higher the rpms go. I checked the balancer and its fine the only other thing i can think of is U-joints. Does this sound right and also can you just put grease fittings in the joints or should you replace the joints with new

 

Replace the joints with ones that have zerks in them already. you might also need to get the driveshaft re-balanced if the vibration is still there. What gear ratio does he have?[8D]

 

Is the vibration only during driving or does it do it in Neutral.
If it is on the road does it do it in all gears at 2500 or just some gears? Does it continue to vibrate if you shift to neutral running down the road?

 

That sounds like a nail in his tire or if he hit a curb or something like that hard it may have bruised his tire either way creating a imballance that vibrates at about 60 to 70 MPH. Try to locate the side and inspect the tire.

 

just when he's driving he does a small vibration when out of gear too but its real bad when driving

 

I would say that it is the joints also, so replace those then see if it still vibrates.

 

i say to re place the joints if it still has bad vibration then go futher

 

what do the motor mounts look like?

 

there fine cracked but fine i checked that too he is putting in new joints today so we will see what happens

 

th U joints werent the problem