Help rearend noise - The 1947 - Present Chevrolet & GMC Truck Message Board Network

LS1 K-5 Blazer · 11-09-2002, 03:55 PM

12 Bolt 71 K-5 four speed.
I posted this in the none specific section but it is really kicking my A**. I looked at the brakes they are fine, change the rearend fluid, everthing looked good for being 31 years old. With rear tires in the air if I spin one of them I get a clicking as the teeth mesh, What is "Normal" noise for one of these.
The noise that concerns me is the one the shows up on deccleration. It is alsmost like a Harmonic, I even get a vibration. It also gets loud when coming to a stop brakes applied or not.
Any help would be great
Thanks!

*Piston* · 11-09-2002, 04:26 PM

When you changed the fluid, do you remember what it looked like? Silvery appearance?

There will be some noise from the open diff spider gears but its something you wont hear while diving. If there is a problem, you'll be able to see pitting on the face of the gear.

If the noise is only on coast/decel, try this... When decelerating put the trans in neutral. Noise go away or get quieter? If so, you'll more than likely find a bad pinion bearing (rear pinion bearing).
If it stays the same, have a quick look at your tires, front and rear. Are they cupped? This will cause a simular sound, just like a bad bearing in the rear end.

It's possible you may have other bearings causing noise too but the noise will not act the same way. Carrier bearings(inside the diff) for instance, you'll hear more noise on accel AND decel between 15-35. Or Front pinion bearing, which causes noise at any speed, decel/accel/coast.

LS1 K-5 Blazer · 11-09-2002, 07:30 PM

Thanks man, you described it exactly. The carrier and spider gears looked good silvery yes, but to be expected. How hard is it to change the pinoin bearing if that it the problem?

LS1 K-5 Blazer · 11-09-2002, 07:35 PM

Oh yeah forgot to mention I have had the carrier out of my z before and was just curious if I pull it apart to get at it and put all the same stuff back in, do I need to adjust the lash and all that?

11-09-2002, 03:55 PM	#1
LS1 K-5 Blazer Registered User Join Date: Aug 2002 Location: Bremerton, Wa Posts: 102	Help rearend noise 12 Bolt 71 K-5 four speed. I posted this in the none specific section but it is really kicking my A**. I looked at the brakes they are fine, change the rearend fluid, everthing looked good for being 31 years old. With rear tires in the air if I spin one of them I get a clicking as the teeth mesh, What is "Normal" noise for one of these. The noise that concerns me is the one the shows up on deccleration. It is alsmost like a Harmonic, I even get a vibration. It also gets loud when coming to a stop brakes applied or not. Any help would be great Thanks! __________________ Mike Friend 2004 Chevy Silverado 4x4 1971 K-5 Blazer

11-09-2002, 04:26 PM	#2
Piston Account Suspended Join Date: Oct 2002 Location: Olathe, KS Posts: 2,300	When you changed the fluid, do you remember what it looked like? Silvery appearance? There will be some noise from the open diff spider gears but its something you wont hear while diving. If there is a problem, you'll be able to see pitting on the face of the gear. If the noise is only on coast/decel, try this... When decelerating put the trans in neutral. Noise go away or get quieter? If so, you'll more than likely find a bad pinion bearing (rear pinion bearing). If it stays the same, have a quick look at your tires, front and rear. Are they cupped? This will cause a simular sound, just like a bad bearing in the rear end. It's possible you may have other bearings causing noise too but the noise will not act the same way. Carrier bearings(inside the diff) for instance, you'll hear more noise on accel AND decel between 15-35. Or Front pinion bearing, which causes noise at any speed, decel/accel/coast. Last edited by Piston; 11-09-2002 at 04:29 PM.

11-09-2002, 07:30 PM	#3
LS1 K-5 Blazer Registered User Join Date: Aug 2002 Location: Bremerton, Wa Posts: 102	Thanks man, you described it exactly. The carrier and spider gears looked good silvery yes, but to be expected. How hard is it to change the pinoin bearing if that it the problem? __________________ Mike Friend 2004 Chevy Silverado 4x4 1971 K-5 Blazer

11-09-2002, 07:35 PM	#4
LS1 K-5 Blazer Registered User Join Date: Aug 2002 Location: Bremerton, Wa Posts: 102	Oh yeah forgot to mention I have had the carrier out of my z before and was just curious if I pull it apart to get at it and put all the same stuff back in, do I need to adjust the lash and all that? __________________ Mike Friend 2004 Chevy Silverado 4x4 1971 K-5 Blazer



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.