metal ticking noise when accelerating
 

96 blazer 4wd...

Not sure if the weather has anything to do with it or not, but all of a sudden when i'm accelerating, i'm hearing a weird noise from under the car towards the rear. It sounds like a metal ticking sound coming from the wheels, but it's hard to tell while i'm driving. It only makes the sound when i'm accelerating.

I know it's hard to explain a sound by typing, but it sounds like metal hitting metal. Not a grinding noise like brakes hitting the rotors. The only way i can thinking of how it sounds is if you've ever watched wheel of fortune. It sounds like the ticking from the wheel as it goes around.

The only thing i can think of is bad wheel bearings, but i'm really not sure since i don't have a lift. Any ideas?

Could be cv in front. I just had a 96 do bout the same thing and it was the front axle stayed ingauged all the time (Vacume Switch on trans was struck). Did not do it in 4x4. Change the cv thinking that was what it was. Sounded like a air plain bout to take off to me. Check if it does it in 4x4 if not could be bout the same problem.

It does it in both 2wd and when 4wd is engaged. It was snowing a lot yesterday so i was able to go in and out of 2wd and 4wd and the clicking stayed constant. It sounds like the sound of someone knocking at your front door of your house... it's that kind of knocking but doesnt go away when my foots on the gas. I let off the gas and it stops, but it sounds like its from the rear or middle of the car.

Unusual noise from under truck
 

The 1st thing I would do is check the driveline u-joints by pushing up & down, rotate & same sequence. They are liable to wear in many different ways like brunnelling. I would check all of them & only purchase ones that you can grease especially if you cross any wet areas while off-roading. If nothing found I would get a jack & rotate each wheel individually & check.

I second NOs

Check the heat shield above your cat and muffler. They loosen and will vibrate on acceleration as well.

So I brought the truck to my mechanic and he's telling me it's the rear differential. He said a couple of the pegs inside the differential cracked and that's why it's making that grinding noise when accelerating.

He wants to charge $600 to fix (400 for parts and 200 for labor. Do I have any choice but to spend the 600 here? Is that too expensive... Usually this guy has decent prices it's just a lot of money.

i would pull the diff cover off and have him show u, before u spend 600 bills, pegs in the diff sounds odd to me. especially in a 3.42 open rearend.

Yeah he said to come down and take a look. I think I'll take him up on that offer. I really don't know what I'm looking for... Is it going to be obvious if it's broke?

ok, i must have missed that part. where did he say he had 3.42's & an open diff?

yeah it should be quite obvious. di dhe happen to tell you what diff was in your truck? like maybe a G80? (would go a long way in explaining the noise).