So I was driving the truck last night and I started to notice a vibration mostly when slowing. It almost flet like chattering over those rumble strips they put on the side of the interstate or exit ramps. When I got to my destination it stopped. On the return trip home it seemed less noticeable then I began to have a vibration at speed so I pulled off at a gas station. The chattering was much worse. So as I looked a round the truck I noticed a stain of oil on the rear diff. I pulled the fill plug and it appeared low and was sorta smoky. The only thing the gas station had was regular motor oil and so I tried that. One circle around the parking lot told me that was going to fix it so I got it towed home.

Today I pulled the diff cover drained the oil and everything looked pretty good very little debris on the magnet. The gears looked pretty good everything looked tight. I really couldn't see any wear at all inside. So I buttoned it back up put new 75w90 in it (synthetic) and took it for a ride and the problems still there.

The vibration it somewhat evident upon acceleration but much more so upon deceleration. It also feels like I have a big set of nobby tires on that smooth out at speed but when slowing down they vibrate really bad. I jacked up the rear any everything appears to be tight and spinning freely.

It's been about 20-25K since I changed the diff fluid. I have 40K on it now. It's a 2004.5 quad cab long bed with the nv5600 and 11.50 4.10 ratio. I don't really haul anything heavy and I've been running 315/70/17 H2s forabout 15K.

 

same thing happened to me. Check your u-joints

 

I've been looking but I don't see anything. Which ones did you have problems with and how did you diagnose? Thanks Shawn

 

Anybody ever have problems with their hanger bearing?

 

It is verry hard to see a bad u-joint unless it is just plain old tore up. When mine went bad there was vibration comming from the rear end while slowing and under breaking, little to no vibration during acceleration. My was still under warrenty so I let the dealer fix it. I belive that bad U-joints are some what common in our trucks

All of the people I know with similar trucks have also had problems with the U-joints

I think NAPA has the proper replacement U-Joint If you want to replace them yourself. I would just replace both rear U-joints with greaseable ones if I had it to do it over

 

fixed
Last week my truck developed a vibration. I have a 2004.5 with 40K. I don't really tow heavy or abuse my truck. I've had H2's on for about 15K. The vibration showed up first upon decelerating, then at speed on the interstate, then the vibration upon deceleration became extremely violent. It felt like I was running over some rumble strips. When I jacked up the rear on my truck and put it in gear the complete driveshaft shook from the transfer case back through the drive shaft. We were able to stabilize the transfer case but there was still alot of vibration. I didn't have any ticking, and the shaft seemed to spin freely. I dropped the shaft and 2 of the 3 u-joints didn't spin freely. I had the 3 u-joints replaced and the hanger bearing. The hanger bearing was damaged due to the violent shaking of the drive shaft.

The shop that replaced the joints said the one of the u-joints just had dust where the needle bearings used to be.

The hanger bearing they used was just a universal style from Napa it's the same bearing size but it hangs 1/4 inch lower. It actually seems to have improved my driveline angle. This bearing was 60 the dealer wanted 160.

U-joint from Napa Item#: NUJ2300188
Attributes:
Type:Standard Joint
Dimensions:1.3750 x 1.3750 Brg. Dia. x 4.1880 x 4.1880 Overall Length
Features & Benefits:w/Outside Snap Ring

Hanger Bearing Item#: BRGHB88508