Mav2u
1/2 ton status
Okay, I'm adding the gear lube recommended for the rear but the the only thing they have at the parts store is this limited slip additive. Will this stuff work good in a Gov-lock limited slip rear?
CK5
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Gov lock limited slip additive?
- Thread starter Mav2u
- Start date
Mav2u
1/2 ton status
It states in the GM mechanics manual the additive is required for Gov Lock differentials!!
Trust me! I didn't add it it my first 10 bolt diff an it ate itself up because I didn't put it in! I was young an stupid back then!! I've since learned to put the additive in. I just don't feel like buying it from the local GM shop this time an wanted to know if this stuff works as good as the GM additive!!
Trust me! I didn't add it it my first 10 bolt diff an it ate itself up because I didn't put it in! I was young an stupid back then!! I've since learned to put the additive in. I just don't feel like buying it from the local GM shop this time an wanted to know if this stuff works as good as the GM additive!!
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Wrong...a gov lock works by a speed/slip sensing govenor engaging the clutch packs.
NO additives....just use the right (equivalent) fluid only.
LOCKING DIFFERENTIAL LUBRICANT (SERVICE INFORMATION) #91-4-109
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 with SAE 80W-90 GL5 (P/N 10950849).
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.
VEHICLES/COMPONENTS INVOLVED: ------------------------- ---- Some light duty trucks equipped with locking rear axles, RPO G80.
SERVICE PARTS INFORMATION:
Part Number Description ----------- ------------------ 10950849 Lubricant, Rear Axle (1 litre)
Parts are currently available through CANSPO.
WARRANTY INFORMATION:
As specified in Light Duty Truck Maintenance Schedules, locking rear axle fluid drain and refill is required owner maintenance at the first engine oil change. Failure to drain and refill the rear axle as specified may contribute to a later axle chatter condition. Refer to the appropriate Light Duty Truck Maintenance Schedule or service manual, section OB, for further details on change intervals.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
© Copyright General Motors Corporation. All Rights Reserved.
I was a little surprised to see the clutchs in it myself. In my 95 Burb 10b, my fluid was black from them burning up, and that was ok, because then I didn't have to worry about it blowing up when the gov kicked in to lock the other axle in. My 9.5 in my 99 has the same setup, and I go easy on it, for fear of the inevitable damage if abused....
as seen below it should work in forward or reverse up to 20mph. If the gov mechanism senses a differential of 20mph the flyweights engage the locking mechanism, and the clutch discs absorb the "shockload" and lock up the carrier as one unit.
here is a nice way to show how it works:
http://www.youtube.com/watch?v=tTGZOJQQBeE&NR=1&feature=endscreen
[youtube]=tTGZOJQQBeE&NR=1&feature=endscreen[/youtube]
as seen below it should work in forward or reverse up to 20mph. If the gov mechanism senses a differential of 20mph the flyweights engage the locking mechanism, and the clutch discs absorb the "shockload" and lock up the carrier as one unit.
here is a nice way to show how it works:
http://www.youtube.com/watch?v=tTGZOJQQBeE&NR=1&feature=endscreen
[youtube]=tTGZOJQQBeE&NR=1&feature=endscreen[/youtube]
Mav2u
1/2 ton status
So I guess I'll just add the 3 qts. of 80-90w Lucas oil in the rear an skip the additive then!!
owenst7
1/2 ton status
It would be a killer design if they just refined it a bit. In the 10.5", running one less spider gear was just retarded, and one of the side gears is really thin at the splines. Had the G80 carrier setup actually been designed stronger instead of weaker than the open carrier, it probably would hold up pretty darn well. That, and I think it should engage sooner to reduce the impulse load. In stock form, it doesn't engage until you really have your foot in it. Not sure what the thought was there, as having the diff go from open to spooled instantaneously with the tires at high speeds isn't the smartest thing for handling either. Sure would make for some fun donuts on the ice though!
Mav2u
1/2 ton status
You can do that by getting a softer spring for the governor.
You can change the spring in the Gov-lock to make is engage sooner and softer?
owenst7
1/2 ton status
You can do that by getting a softer spring for the governor.
I know, but it still doesn't address the issue of only three spider gears.
Its a cool design, but its a shame they implemented it so poorly.
