Wheel bearing noise

Bad u joint? Wheel bearing? Jack it up off ground and run it in gear while someone else isolates noise source.

3 possibilities could be wheel bearing, cv axle or a unbalanced tire.

You will need a blanket and a flashlight.
One way to get the truck high enough to look under it is to drive either the right side wheels or the left side wheels up onto a curb.
Then get under it and look halfway between the end of the transmission and the rear axle pumpkin.
A carrier bearing is the round thing about half way between these two.
Just a little more information.
The carrier bearing is found roughly about the place where the back of the front seat is above you. The carrier bearing is likely the size of a breakfast cereal bow,l, .
The pumpkin is the big gear holder exactly in the middle between the rear wheels, and is about the size of a large dinner plate.
Your vehicle is old enough to need one if you have not had it replaced yet.
These normally will give you some notice of their failure, such as a vibration or noise of some kind, be not in every case.
Be blessed.

i assume you mean **** when you type *****,just say ****.this sounds like the rear tires may be out of blance or has a defect in the tire(s).a wheel bearing won`t cause a vibration unless the bearing is so bad its about to or is coming apart.a wheel bearing will make a noise like a humming or growling noise.have teh wheel balance check and the condition of the tires checked for belt separation or bulges.

Check if there is some debris or obstuction in the wheel well. Also check the tread of the tires for uneven wear.

Put the car on a jack and try to move the wheel up and down. If it does so with clanking sound, your wheel bearing is defective and needs to be replace. For the uneven wear on your tires, you need to get an alignment for your car.

the smell of trans fluid indicates that it's overheating, either needs changing, if your lucky, or a more involve drepair , get the OBD codes read

Run hot wire from battery stright to bat. side of coil and see what happens.

Either the tires have slippe belts in them, mainly old or worn tires. Or more common is one of your wheel bearings is going bad. Could also be an axle shaft. Jack up the front of the vehicle and grab the wheel and see if you can move it up/down or side to side. see if there is excess play to check wheel bearing issues

We had a 99 model LS and the caps just popped off and on. Only held on by friction fasteners.

I had this problem on my 1995 Montero. The 4-wheel-drive indicator lights wouldn't stop blinking when I switched from 4-wheel drive to 2-wheel drive. It turns out that I had a slow leak in one of the front tires. After I fixed the leak and made sure the pressure was the same in both front tires, the problem went away. 
This made sense to me because if one tire is much lower in pressure, it's closer to the ground, i.e. has a smaller radius, and therefore rotates more quickly. The manual says to drive in a straight line when disengaging 4-wheel drive but with the lower tire pressure on one side it was the equivalent of driving in a circle. 
You could try checking your tire pressures and see if that makes a difference. Hope this helps.