1990 Chevy CK1500 2 wheel drive pickup - Rear end

my guess is the wheel bearing. jack the rear tire off the ground and try shacking the tire. if you have any play your bearing could be bad.did you hear a hum from the same wheel. wheel bearings will hum before they start grinding

grease ur differential ur rear end get underneath find all ur grease zerts and ask a shop how to grease ur rear end

if it is a 4 wheel drive sounds like your rear axle may have been cooked do to low fluid bad bearing or both check fluid level nad look for any kind of metal specs in fluid .

Jennifer what type of timing belt does your engine use ?
Is it Nylon ? When was the last time you had it changed ?
Burning plastic smell may be being caused by the timing belt bearing runners seizing and the belt is getting hot .
If the belt is due to snap you could cause a lot of damage to the engine if it breaks.
Might be worth getting a mechanics advice on this as a possible cause

does it get louder above 45-60mph? and much quieter at low speeds. It could be wheel bearings, a rear differential or front differential. If its a grinding humming noise its wheel bearings, listenin to see if theyre coming from the front or rear, left or right, or both when your driving to know what wheel bearing are bad. If its a whinning noise, its probably a differential. check and listen to hear if its coming from the front or rear. Also, check for loose plastic around the wheels. Lastly check your tires for uneven or choppy wear. move your hands front to back on the top of the tire. does it feel really choppy and rough, maybe you just need new tires

ok it could be two things. it could be rear wheel bearings or a rear diff. If its a high pitch wine then its worn gears in your differential. its needs serviced or replaced. If it more of a rumbling or grinding hum, coming only from one side or both) then there are bad wheel bearings.

When does the noise occur, while driving only, or driving and idle, in gear, or in neutral and park? If it occurs all the time (while driving and at a stand still in cold weather) it could be the fuel pump. If it occurs only while driving, it may be a wheel bearing. Describe the noise (humming, grinding, whirring, etc), and what is the mileage on the Pilot? Answer my questions so I can fine tune my answer. Thanks!

Watch out! You might have a loose wheel! Check those wheel nuts. If not, a loose brake caliper, or last if not least, a bad wheel bearing. Don't drive it until you find out what the heck is wrong! Could be dangerous.

Yes it is a 700R4. They went to a 4L60E in 1993. Good Luck