Starting about a week ago I've been having some wierd issues with my rear axle.
1. when taking off(usually from being park or reverse) I get some metallic clicks/clanks coming from the rear end.

2. When making a right turn(not matter how slight) or even being on an angle where weight is shifted to the driver's side I get a scuffing/whining sound which sounds like it's coming from one of the wheel bearings.

3. Biggest issue is when I get over 35mph, the whole vehicle starts to vibrate pretty severely, feels kinda like I have a loud subwoofer rumbling or have those snow cables on my tires. This sound only happens under throttle, for example: if I'm running at 50mph it will be vibrating like crazy, if I take my foot off the gas or switch into N the vibration stops, if I so much as tap the gas the vibration comes back, I don't need to be accelerating or even holding speed, just giving it any throttle at all.

I'm thinking maybe one of the wheel bearings are bad but not sure if that would cause all these other issues.

Jack up the Montero and start poking around. Pinion bearings, u-joints and other wobbly parts after all these years.

Jack up the axle side that's loaded when it's noisiest, and pull the wheel and brake drum. Try to wiggle the axle flange in/out, up/down, right/left, and feel for slack.

While it's still up, crawl under and turn the driveshaft and feel for ujoint slop or bind, and look for smooth movement of the spider in the bearing cups, both front and rear.

Well looks like the vibration and clunking was the rear u-joint. Removed the drive shaft and sure it enough it was long gone. I also drove around without the rear shaft and no clunking and no vibration.

I still get the squalling/scuffing noise when turning right or any time the vehicle weight is being shifted to the driver's side. I will pull the driver's drum and check for slack in the bearing. Maybe I need to add or remove a shim from where the backing plate bolts to the axle tube???

Did you loose any fluid out of the T-case. If not, it may be empty ...suggest you check that too.

nothing spilled out when I removed the drive shaft but when I got home there was some fluid on the crossmember that had dripped out. I will check the fluid level.

Probably wouldn't be a bad idea to check fluid levels, switch to synthetic in the rear axle too.

For future use, I did some research (a lot, actually), and the shaft size for the rear output seal is 40mm, or about 1.574798". I'd try to find the expended case from a blooker or a Bofors for a plug <img src="/forums/images/graemlins/smile.gif" alt="" />....