G80?

[Prospect62]

My RPO list says I have a G80. When I had the truck up in the air the other day, I spun the rear wheels and when one went forward, the other went backward. Any shadetree mechanic worth his salt will tell you that this would tend to indicate an open differential.

If I truly had the limited slip, both wheels should turn in the same direction. That's how it's always worked before, anyways.

Anybody know what's going on here? Does the good 'ol G80 work differently in this truck as opposed to the 5 or so other Chevy trucks I've had before?

 

[iamdub]

The type of locking differential these come with engages when there is a 120 RPM difference between the two sides. Look up "Eaton Gov-Lock". It's more befitting to call it a "limited spin" rather than "limited slip".

During normal driving, it acts like an open differential. It's actually a great idea in that, when locked, 100% of the power goes to both wheels, just like a true posi. With a limited slip that uses clutches or gears, there's still slip happening so you won't get full power to both wheels. When they wear out, they can act like having a standard open differential. The G80 just isn't stout enough for heavy off-road or high-performance use. It can grenade if overloaded, hence the nickname "Gov-Bomb". If you don't beat on it and keep clean fluid in it, it should last you a while.

 

[Doubeleive]

When it does take a crap throw a eaton detroit trutrac in there, no more problems, better to spend a little more and get something that probably wont ever break again

 

[iamdub]

When it does take a crap throw a eaton detroit trutrac in there, no more problems, better to spend a little more and get something that probably wont ever break again

Dis muhfuh spittin.

 

[Prospect62]

The type of locking differential these come with engages when there is a 120 RPM difference between the two sides. Look up "Eaton Gov-Lock". It's more befitting to call it a "limited spin" rather than "limited slip".

During normal driving, it acts like an open differential. It's actually a great idea in that, when locked, 100% of the power goes to both wheels, just like a true posi. With a limited slip that uses clutches or gears, there's still slip happening so you won't get full power to both wheels. When they wear out, they can act like having a standard open differential. The G80 just isn't stout enough for heavy off-road or high-performance use. It can grenade if overloaded, hence the nickname "Gov-Bomb". If you don't beat on it and keep clean fluid in it, it should last you a while.

Informative, thank you. Never knew the current G80 changed from the old G80.

 

[Dantheman1540]

Informative, thank you. Never knew the current G80 changed from the old G80.

I don't believe they have changed in 50 years you just need to spin the tire faster for it to see the 120rpm difference and then lock, sending both tires the same direction.

 

[Prospect62]

I don't believe they have changed in 50 years you just need to spin the tire faster for it to see the 120rpm difference and then lock, sending both tires the same direction.

Oh...I thought it was some updated version of the G80.

Every G80 I've had before, I haven't had to spin the tires fast at all. If they spin the same way - limited slip. If they spin opposite ways, open.

I dunno.

 

[Tiredmechanic23]

The type of locking differential these come with engages when there is a 120 RPM difference between the two sides. Look up "Eaton Gov-Lock". It's more befitting to call it a "limited spin" rather than "limited slip".

During normal driving, it acts like an open differential. It's actually a great idea in that, when locked, 100% of the power goes to both wheels, just like a true posi. With a limited slip that uses clutches or gears, there's still slip happening so you won't get full power to both wheels. When they wear out, they can act like having a standard open differential. The G80 just isn't stout enough for heavy off-road or high-performance use. It can grenade if overloaded, hence the nickname "Gov-Bomb". If you don't beat on it and keep clean fluid in it, it should last you a while.

just to throw my 2 cent in. I have beat the hell out of multiple trucks with a G80 and never blew one up. If you use the right fluid at the right interval and do not rev to all hell when your tires slip it should not blow. They blow when people peg the RPMs before they engage so they engage hard or from people using the wrong fluids with LSD additive causing them to slip or engage late and lock hard and grenade.

 

[George B]

Oh...I thought it was some updated version of the G80.

Every G80 I've had before, I haven't had to spin the tires fast at all. If they spin the same way - limited slip. If they spin opposite ways, open.

I dunno.

In the trucks its the one Iamdub described but a G80 in a car would be a limit slip if I remember.

 

[Doubeleive]

just to throw my 2 cent in. I have beat the hell out of multiple trucks with a G80 and never blew one up. If you use the right fluid at the right interval and do not rev to all hell when your tires slip it should not blow. They blow when people peg the RPMs before they engage so they engage hard or from people using the wrong fluids with LSD additive causing them to slip or engage late and lock hard and grenade.

lol, I have broke at least 3 real good, maybe 5 and never spun the wheels or dropped it in gear while revved or anything, the G80 is weak in my book, I haven't broke a eaton detroit I did wear the bearings out though. my current Denali has the g80 it was replaced shortly after I bought the vehicle under warranty, being it is AWD it takes some of the strain off of it so it may hold up longer than usual and I put a girdle on it so time will tell. The ones I have broke were maintained annually around every 10-15k. I guess it just depends on how you drive, I drive mine hard but no wheel spins or stupid stuff unless it happens while going around a corner or something. Also maybe the traction control saves it a bit, there is a place I often go over the curb to get around traffic and the traction control kicks in and makes it hesitate for a second