gmc forums   gmc forums
Go Back   GMC Forums > GMC Vehicles Currently In Production > GMC Sierra Forum

GMC Sierra Forum Forum for discussions regarding the GMC Sierra


ATTENTION: We're looking for moderators. Is anyone interested?
GMC Forum: limited slip rearend
Reply
 
Thread Tools
  #1  
Old 06-29-2010, 10:09 PM
brushish brushish is offline
Junior Member
 
Join Date: Jun 2010
Posts: 2
Default limited slip rearend

I have a 2000 z71. This is the second one i have owned and was never happy with the limited slip on them. I found locker would kick out if the wheels got to much traction and only one wheel would spin. Is there an upgrade that doesn't cost to much that i could do to my rearend to make it a better locker system?
Reply With Quote

  #2  
Old 06-29-2010, 11:05 PM
Molson02536 Molson02536 is offline
Senior Member
 
Join Date: Dec 2009
Location: K/W Ontario Canada
Posts: 3,098
Send a message via AIM to Molson02536 Send a message via Yahoo to Molson02536
Cool

Quote:
Originally Posted by brushish View Post
I have a 2000 z71. This is the second one i have owned and was never happy with the limited slip on them. I found locker would kick out if the wheels got to much traction and only one wheel would spin. Is there an upgrade that doesn't cost to much that i could do to my rearend to make it a better locker system?
Your rear is probably garbage like mine was, mine had a mind of its own sometimes it would decide to let me drift it sometimes it would just one leg. It eventually broke and seized in the lock position and ended up with a Jimmy that loved doing donuts, that got old quick so i went and bought a detroit trutrac limited slip differential. It runs about $900.00 or better but worth it, got my Jimmy turned in to AWD now and needed the G80 rear end cause of the AWD transfer-case. You might want to try the GM TSB and service your rear end with the full synthetic Mobile1 limited slip gear oil.

http://www.eaton.com/EatonCom/Produc...trac/index.htm

http://www.mobil.com/USA-English/Mot...ollection.aspx

Last edited by Molson02536; 06-29-2010 at 11:35 PM.
Reply With Quote
  #3  
Old 06-30-2010, 11:40 AM
Z15 Z15 is offline
Senior Member
 
Join Date: Jun 2010
Location: Michigan
Posts: 443
Default

First of all trucks don't use a limited slip differential unless is a All Wheel Drive (AWD). An AWD will not have any means to disengage it. Limited slip differentials are normally installed in cars, my AWD CTS has a limited slip. Every GM truck I have owned going back to the early 1980 has had the G80 locking differential. I never to this day have had one issue with it and fail to see what all the complaining is about. It has got me thru some terrible winter and down some bad woods roads and never had gotten stuck.

One thing that can screw up the truck G80 is adding a limited slip additive to it, NEVER do that. You would not believe how many do this because they are misinformed about the rear axle in trucks. They figure, what can it hurt. Read below...

Since the '80;s GM uses the Eaton Automatic locking rear differential in all trucks & SUV that are not AWD. Note-AWD can't use a locking differential because of the transfer case used. The AWD operates differently than a 4x4.

What this
http://www.youtube.com/watch?v=-sw9DwurQAs
http://www.youtube.com/watch?v=tTGZOJQQBeE
http://www.youtube.com/watch?v=q-rQTHMVAuw

Quote:
SUBJECT: LOCKING DIFFERENTIAL (G80) LUBRICANT - (SERVICE INFORMATION)
VEHICLES AFFECTED: ALL LIGHT TRUCKS EQUIPPED WITH G80 REAR AXLE ALL YEARS

Some light duty trucks equipped with locking rear axles (G80) may exhibit rear axle chatter, especially when turning a corner from a stop.
This condition of alternate engagement and disengagement of clutches in differential assembly is usually caused by contaminated axle lubricant.
To correct this condition, drain and refill the rear axle. The use of any additive in locking rear axles (G80) is not recommended. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. All light duty trucks equipped with RPO G80 make use of a locking differential and the use of additives will delay the engagement of the locking mechanism and may decrease axle life.

Last edited by Z15; 06-30-2010 at 12:10 PM. Reason: correct typos and add links
Reply With Quote
  #4  
Old 06-30-2010, 03:02 PM
Molson02536 Molson02536 is offline
Senior Member
 
Join Date: Dec 2009
Location: K/W Ontario Canada
Posts: 3,098
Send a message via AIM to Molson02536 Send a message via Yahoo to Molson02536
Cool

Quote:
Originally Posted by brushish View Post
I have a 2000 z71. This is the second one i have owned and was never happy with the limited slip on them. I found locker would kick out if the wheels got to much traction and only one wheel would spin. Is there an upgrade that doesn't cost to much that i could do to my rearend to make it a better locker system?
Here you go friend.

On 1999 model year Sierras and up GMC trucks use an exclusive locking rear differential. In fact, it's standard in many models. The locking rear differential senses when one wheel is slipping and transfers power to the wheel with the best traction. When a rear wheel loses traction and its speed exceeds the other wheel by approximately 100 rpm, a governor triggers a cam system that activates multiple disc clutches. The clutches become self-energizing and both wheels are locked together for maximum traction. At vehicle speeds above approximately 30 km/h (you're obviously not stuck if you're going this fast), the governor is prevented from applying the locking clutches so the unit operates as a standard open differential at normal road speeds or when not needed.

Competitors attempt to solve this problem with an optional "limited slip" differential. A typical limited slip design incorporates clutch packs between the axle side gears and differential case. A set of springs puts a constant preload on the clutches so they're dragging all the time a situation that can cause unpleasant chattering on turns if not properly maintained. Primary clutch engagement is produced by the shape of the teeth on the differential gears, which tend to push apart when driven. When torque is applied to the axle, the side gears are pushed apart to further engage the clutches. However, the slipperier the road surface, the less torque load on the gears before tire slippage occurs and therefore the less clutch engagement to solve the problem.

Feel free to ask any questions if still confussed.
Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT -5. The time now is 09:37 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
gmcowners.com recognizes that "GMC", it's logos and various model names and numbers are registered trademarks of the General Motors Corporation. These terms are used for identification purposes only. gmcowners.com is not affiliated in any way with the General Motors Corporation, GMC or any other company listed herein. All information on this site is the opinion of its members and not the opinion of the site itself. 2014 Madison Ross Media Group. All rights reserved. Content published on GMCOwners.com requires permission for reprint.
MADISON ROSS MEDIA GROUP MARKETPLACE
Need products for your GMC Truck? Check out your options at the links below:

No special deals available at this time...