Does Your Car Have A Slight Vibration

Had this lady with a Dodge Dakota pickup that had aon the rear u-joint--Ah ha! The joint had just a little bit
slight vibration.of slack in it.
She told me she thought it was the tires; she had themWhen I removed it from the drive shaft I removed the
put on a couple of months ago.cups.
She took the truck back and had the tires balancedTwo of the cups were almost completely void of
again, but it didn't seem to help.grease and the shaft on the cross had 'ridges' where
I drove it down the road and noticed it did feel likethe needle bearings had been riding on it...without
rough pavement, sorta like little 'ribs' across the road.grease, it had worn groves in the shaft, causing the
I noticed when I gave it more fuel or let off of theslackness...causing the vibration.
accelerator, it would quit vibrating...it smoothed out andWhen a universal joint gets a little slack, and you have
ran like a Dodge ortta.it balanced at, say 55mph, then it will vibrate.
I put it on the lift and raised it to where I could turn theIf you let off the accelerator, or push the accelerator,
tires. No noise. I shook each one back and forth. Noyou put the drive line in a bind. When it gets in a bind, it
looseness in the bearings or tie rods.quits vibrating.
I thought it could possibly be a bearing in the differential.After installing a new universal joint and replacing the
I turned the rear wheels but didn't hear any bearingdriveshaft, there was 'no' vibration when I test drove it.
noise, so I started checking the universal joints in theShe was so proud of me...she cooked my favorite
drive shaft.meal, pork-chops, and invited our children over for
No slack that I could feel or see.supper.
I took a large screwdriver and pried against the cross