well a little back story for you guys..... for about a month or two something in the back of my truck has been whining and grinding. i was going to summer university and didn't have time to do hardly anything except homework and sleep. university got out yesterday and i decided to check it out. a week or so ago i posted about the very same problem, and one of the suggested solutions was to check the differential fluid. today, like i said, i got around to checking it. so i opened her up and drained all the oil and washed everything with a little gas and made sure to wipe the metal out. there wasn't a lot of metal or any big chunks in it. then i put everything back together and let it sit, filled it up and went to take a little break. after and hour or so i took the truck for a spin. before i changed the diff oil it wouldn't whine when i got up in the morning to go to school as i was leaving. but once i drive a while i guess everything get warmed up back there after about 15 or 20 miles. then whenever i made a complete stop at a light or whatever it would grind very little for a couple of seconds then it would go away a speeds faster than like 10mph. and when i stopped completely and then made a hard right turn i would grind pretty bad then go away once straightened or so. after i changed the oil and drove it about 20 miles or so i decided to take a little test to see if it had fixed it. and lo and behold it's about half as bad but still does it. and sorry for the rather long post but to finally get to the question is it going to get better over time now that i have changed the diff oil or will it just keep getting worse. i now think it might be the axle bearing but my does have 170,000 miles so...

 

axle bearing. mine did it for the longest time and I finally got around to replacing all the bearings and the ring and pinion (even though it wasn't needed) and it's so such a quite ride now. I love it

 

how much are they and is it hard to install? btw its the driver side, i dont know how much harder it would be to get the axle out of the gear box

 

I'm not sure, I helped my Uncle and he showed me how to do it. Didn't seem to be that difficult at all with the right tools. Just pulled the tire off, took the drum brake cover off and yanked the axle out, then used a tool that pulled the bearing right out.

 

download the service manual here.
http://www.rm-indy.com/wavefiles/2001ramsrvcmanual.zip

you've got al lot of moving parts the center diff - pinion bearing, pinon gear, ring gear, spider gears, and carrier bearings. then you've got axle bearings out at the end of the axle tubes.

the axle bearings (and seals) are pretty easy. the service manual above will show you how to change them.

all the center pieces are not really a shade tree diy and will require a setup by somebody that really knows what they are doing, although some people do just slap it together and it works out ok.