Ok. Long story short, Im about to kill this truck. =/ I have a 2000 Ram 1500 5.9l Ext Cab, automatic, 4x4.. I have owned it 2 years, it has 216k miles. Aside from having literally almost replaced everything, It is currently in the shop for Power Steering pump, and gear box replacement. Now, They Just called me, about a noise, and vibration when letting OFF the gas, coming from the rear end and said its most likely a Pinion Bearing. However, it has had that "Bearing " like noise for a long time. It only happens when you ARENT touching the gas pedal. If you even so much as inch a toe on it, it stops. I do NOT have a catalytic Converter on it, and the pipes and criss crossed in two places just behind the Motor, to keep it from throwing an 02 Sensor code. (Dunno if it works, I bought it this way and there is no 02 Sensor issues) Regardless, I tried to explain to them Its always sounded that way. I have not noticed any vibration other than road vibrations. My question? Since this noise is ONLY when its coasting, and does NOT depend on the speed and turning of the axle.. Could it really be a pinion bearing? Can I lift the back end of my truck and turn the wheels and tell? Thanks a ton in advance. Im about done with this thing.

 

I would have a look at it, and shake/wiggle the driveshaft, and see if there is any slop. With it up on jackstands, turn the shaft by hand, and see if it feels 'crunchy'. If all checks out, and it isn't leaking anything, let it go.

 

Thank you. I will get it up and check it out for sure. I haven't noticed any leaks on it at all, and I have had it up on the lift twice inspecting. I wasn't really looking for that though, so I will double check everything this evening when I get it home.

 

Pay attention to the u-joints as well.

 

I did inspect ALL those about a year ago, and in fact have replacements at home on the shelf, trying to trace down a bad ujoint that ended up being on the front 4x4 shaft. Sounds like a good time to double check them again. Thanks!

 

Okay. I just hoisted the rear end up, and climbed under it. Turning the wheels is nice, noise free and solid. Except the normal tick when going from forward to backwards. HOWEVER. I did noticed some in and out play in the bearing behind the u joint going into the rear axle. Minor, but still there. Everything else is solid. This is the Rear Axle Pinion Bearing, right? Give it to me straight, how much crap am I lookin into replacing this on my own. I can easily drop the drive shaft.. I know I will have to drain the fluid..

 

Complete and total disassemble of the rear end. With all the right tools about 3 hrs work. Right now your parts list is small and cheap let it go and it can get much more expensive.

 

I drove mine for a couple years listening to the pinion whining. Finally turned into a shudder when slowly turning from a stop. Clutch packs and new bearings replaced for around 750.00 took care of the whine.

 

Yup... I've got about 30k of "whining" on my rear axle... it isn't getting worse, and no other sounds of deterioration.
It's on my list of stuff to do, but not a priority at this point.

 

Keep in mind that the pinion nut is no longer tight when there's slack in the bearings. Mine never made a sound until the nut came off and the ring gear pulled the pinion inside pretty much destroying everything in there.