I'm fighting a driveshaft vibration problem and looking at the center bearing and double C as the culprits.

Can someone tell me how to check the center bearing? I can grab the driveshaft and move it from side to side a bit. It does not have any loose slop. The rubber cushion just gives and allows it to move. Is this normal? How much movement is allowed?

Any advice on how to check the double cardan joint would be appreciated as well. I plan on disconnecting the shaft and looking at the joint closely on a bench. I don't see any slop in the joint at all but it could be binding.

Thanks,

Shedman

Slight movement from the rubber is normal. The way I check for worn parts in the drive shaft is to rock the truck back and forth by hand with it in park or in gear (engine off). The rocking motion will show any back lash in the u-joints. Look for any movement of the inner sleeve inside the bearing caps of the u-joints.

John