I just bought a 98 explorer 2WD, everything else works great, I think its just the tires, but Im not sure, any sugestions if its not the tires?

A rear end could possibly give you a whining noise if fluids are low, although it would probably not last long before you see other issues. If it's a constant whine (does not chage when getting on or off accelerator) then it's probably tires. If it changes under load (accelerating or letting off the accelarator) it's probably U-joint or pinion.

Some model years have problems with rear bearings too. It's been discussed in this forum before, so it may be worth searching for.

-Rod

Could be bad bearings. I had the diff carrier bearings go on my 92 a few years ago. $350 worth of new bearings and seals, the rear end was like new again!

I've had bad axle bearings a lot more frequently than other bearings. Listen at each side with the drums off and you should hear it. The vehicle has to be on jack stands. Running in gear at a slow speed.

I've had bad axle bearings a lot more frequently than other bearings. Listen at each side with the drums off and you should hear it. The vehicle has to be on jack stands. Running in gear at a slow speed.

If you try this remember that you don't have any way to stop the tranny from turning before pulling it in park. So turn the truck off before pulling back in park so you don't tear the park pin off on it.

If you try this remember that you don't have any way to stop the tranny from turning before pulling it in park. So turn the truck off before pulling back in park so you don't tear the park pin off on it.

Very good point! Additionally, since you would have the drums off at this point, be sure not to attempt to apply the brakes as you will force apart the wheel cylinder (or caliper piston if you have rear disc) and create a real headache.

-Rod

True, You shouldn't press the brake when the brakes are apart, however, It is an excellent learning example! When you do it once, you'll never do it again! That's how I learned! Never do that again.

Any luck on the Diaganosis Dennis D?

Does the noise stop when you let off the accelerator? My 98 Explorer does the same thing. It is not as loud now that I put a quart of oil in the rear end. It sounds like these guys are right on with the rear bearings going bad. I replaced my U-joints and it made no difference. It still makes the noise with a new set of tires also.