truck shutter and rpm drop

[JNehl]

Looking for a diagnoses, I am hoping its not too harsh on the pocket book. When I slow down to stop my truck shutters. It vibrates just a little bit at higher speeds. I thought it might be the u-joints; truck has 54000 miles with original joints and lots of towing. Also when I a slowing to stop my rpm's drop to 500 before it goes back up to normal. I have a small leak between the transmission and transfer case. I plan on starting with the ujoints since they should probably get changed anyhow.

 

[JNehl]

I thought bad u-joints would cause the vibration to get worse at higher speeds? Would bad u-joints cause the engine to lug at lower speeds causing the rpm drop?



There are no codes.

 

[HOBrian]

Sounds like a bad u-joint. At what rpm are you pushing in your clutch?? I can't think if mine does that or not.

 

[JGoss]

My rear driveshaft u-joint went bad at about the same miles as yours. There wasn't much play in it, but enough to cause the vibration similar to yours. At first I thought it was the tires, but after replacing them(which they needed to be) I still had the bad vibes. Hope this helps