I have a 93 p-u that has a vibration upon deceleration at 25-30 mph and lower, usally when down shifting to 3rd and 2nd.

It sounds like tires humming to a stop but I can feel it. I had recently changed the tires and although they were similar in tread, in still get the same noise, so I ruled out the tires.

I get no vibration at all on acceleration.

I had replaced the one u-joint because it was obviously bad.

Is it possible that the other u-joint is bad even though I can not physically wiggle it?

Is it in the rear end?

Thanks

 

Yes, it is very possible. Your drive train puts a hell of a lot more torque on that shaft than your hands ever could.

 

x2 on the u-joints

 

could very well be a u-joint.

When I had my front end lifted, and the rear sitting about 1.75" lower it braked a little weird, almost a vibration. It braked harder with the rear even though the rear end was empty due to the angle of the LSPV.

After i finally got the rear end up my braking issue dissapeared.

 

I 3rd it

 

Do you have any sort of lift on it? If so keep in mind your pinion will tend to rotate up when accelerating and it will rotate down (away from the Tcase) when you are decelerating. So if you are near the working limits of your Drive shaft decelerating may exceed those limits. IF you don't have a lift then Im with every one else and its probably a U-joint.

 

Could be pinion angle couldnt it?

 

It's most likely going to be your ujoint. You can't get an accurate inspection from just gr4abbing it. Your drive train is always in some sort of bind or pressure even in park. I would suggest taking it some were$$$ reguired. Or pull the driveshaft and inspect the ujoints loose. look for metal rub or rust or excess greese and any play in the ujoint.