G80 diff didn't lockup

Ripshift · 10-30-2011, 12:46 PM

I backed the R out of the driveway to shovel the snow (that's rite) and when I went to pull back in the right wheel started spinning and spinning. I hoped the gov-loc was going to lock the clutch pack and the left wheel should have grabbed the bare tar, but NO!

I let it spin and gassed it a few times then it started to make a funny noise so I stopped.

The off road forums don't care for the g80 but found some good rebuild info. I wonder if I broke the gov-lock with all the burnouts I've done

I'll go in and take a peek.

BlueStreak · 10-30-2011, 12:57 PM

Good Luck. I hope it is not too expensive.

twooldfarmers · 10-31-2011, 06:04 AM

keep us all posted as alwayswe can all learn from these incidents at the same time.

Topspin · 10-31-2011, 08:20 AM

I don't think we have the locking diff. in our rides. It's listed as a limited slip and I believe contains normal clutch packs, which are possibly worn in your case. How many miles on your R?

twooldfarmers · 10-31-2011, 08:37 AM

I had the cover off of mine a week ago for a normal inspection of the magnet and fluid change prior to storage. I found that it is equipped with the 8 1/2 ring gear and a Torsen type carrier that does not have the normal clutch packs that us old guys are all accustomed to with GM rear axles.

a standard type of gear oil is all that is required for a Torsen.

You do not need an oil with an LS designation such as is required for the 9 1/2 inch differential found in six speed equipped R's which does have the normal clutch pack to provide semi lock up.

but this still leaves us all wondering what is going on inside of yours

as a side note.
I purchased an 06' Corvette last winter for my high school Economics teacher. It was cheap because the owner thought the rear end was toast. The noise and vibration was truly indescribable.

I knew that all that was required was an oil change as GM has had a problem until they changed the oil spec sometime during the 2008 model year run.

There a TSB is out on the matter. The additives are precipitating out and leaving the clutch packs devoid of the proper lubrication. Those of you that have not experienced the noise and vibration that transmits back through the body and seats of the vehicle would not believe it until you have experienced it. All it need was to drop the drain plug out of the bottom and in with two quarts of the 'new' GM LS oil.

Mobile 1 LS fluid does not meet GM's specs and if you go to the Mobile web site they even have a bulletin stating the same. 60 bucks worth of oil knocked $5000 dollars off the price of this 18,000 mile cream puff.

Ripshift · 10-31-2011, 10:16 AM

I think I smoked the left side clutch pack from what I've read. The right side always wants to spin so the left clutch pack is always trying to lock.

twooldfarmers · 10-31-2011, 07:48 PM

as a side note here guys

I went looking for some tech info on this and in the process of going through 'my stuff' I found a 2006 Chevrolet Trailblazer show room brochure.

here is what it lists under the heading of MECHANICAL (features) in the back

Limited-slip differential-rear Std on SS
Locking differential-rear Std on LS & LT

my take on this is that the SS Trailblazer uses the same SSR 6 Speed 9 1/2 inch with clutches and the LS LT models have the Torsen which they are designating as a 'locker'

who knows for sure about this?? anybody

ssr71 · 10-31-2011, 07:49 PM

Yes... 6-speeds share the same rear axle as the TBSS.

Here's something I found on a TBSS site:

9.5 14 bolt breakdown - TBSSOWNERS.com Forums - The #1 TrailblazerSS Dedicated Owners Forum[/U]

Topspin · 11-02-2011, 09:10 PM

Yellowssr6spd mentioned the "gov-loc" differential in the first post, and I know my 05 does not have it. Mine came with a traditional limited slip diff. in it, though it has the G80 code which many think represents the gov-loc locking diff. There's some that contend that the G80 designates either diff., and it would appear that could be the case based on my ride. Both are Eaton designed carriers, so I'm not certain if there's a Torsen even made for the 9.5 axle? Anyway, my opinion is all stick Rs came with the conventional Eaton limited slip differential, for whatever it's worth.

twooldfarmers · 11-02-2011, 09:17 PM

Ken my 6.0 L 05' auto has the 8 1/2 Torsen unit in it.

Topspin · 11-02-2011, 09:26 PM

Yep Richard, all autos have the same thing, I was limiting my comments to the 9.5 stick axle.

RSSRTOY · 11-03-2011, 09:47 AM

G80 IS GM's OPTION CODE FOR ALL THERE LIMITED SLIP DIFFS NO MATTER MAKE , MODEL OR SIZE OF THE DIFF.

Ripshift · 11-03-2011, 10:46 AM

Quote:

Originally Posted by Topspin

Yellowssr6spd mentioned the "gov-loc" differential in the first post, and I know my 05 does not have it. Mine came with a traditional limited slip diff. in it, though it has the G80 code which many think represents the gov-loc locking diff. There's some that contend that the G80 designates either diff., and it would appear that could be the case based on my ride. Both are Eaton designed carriers, so I'm not certain if there's a Torsen even made for the 9.5 axle? Anyway, my opinion is all Rs came with the conventional Eaton limited slip differential, for whatever it's worth.

When I had mine jacked up years back I could spin one wheel in neutral. I believe mine has the Gov-loc or the springs between the clutch packs are all broken, and I dont think that's the case. The g/l is a good concept because it acts like an open carrier untill one wheel over speeds the other under power. ie. no chatter when taking a corner easy but should have grabbed in my driveway.