Donuts in the snow. Harmful?

[ZD3SF]

02 Bravada with 236k miles. A guilty pleasure of mine is to do donuts in an empty parking lot behind work as it helps me get in tune with the truck and learn how to correct a slide while in traffic, at least that's what I tell myself. I don't go hard on the revs nor do I fully lock the steering wheel as that can harm the PS pump. More like sliding around and having fun.

I have the front driveshaft disconnected and the encoder motor fuse disconnected. The transfer case wouldn't engage AWD. Fluids in tranny, transfer case, rear diff are all new. Rear diff is a locking G80. would that do any potential damage to the transmission/ PS pump, rear diff, or transfer case?

 

[TJBaker57]

02 Bravada with 236k miles. A guilty pleasure of mine is to do donuts in an empty parking lot behind work as it helps me get in tune with the truck and learn how to correct a slide while in traffic, at least that's what I tell myself. I don't go hard on the revs nor do I fully lock the steering wheel as that can harm the PS pump. More like sliding around and having fun.

I have the front driveshaft disconnected and the encoder motor fuse disconnected. The transfer case wouldn't engage AWD. Fluids in tranny, transfer case, rear diff are all new. Rear diff is a locking G80. would that do any potential damage to the transmission/ PS pump, rear diff, or transfer case?

I think you could grenade your G80. They are not designed for this.

 

[ZD3SF]

Gotcha. Better stop then.

 

[fletch09]

Have not done that for few years, but loved doing it w/ first snow of season. Told myself, as you have, to help re-familiarize how it handles in snow. Did turned off stabillitrac and traction control, before doing so.

 

[littleblazer]

Could potentially break the PS pump if at full lock too. My shaft snapped at full lock backing out of an awkward driveway.

 

[Mektek]

With a regular differential it would be OK since each drive wheel is free to slip. A G80 is designed to fail if one axle shaft has too much load or shock. The official GM promo video shows the truck being driven with a locked G80 and a single traction wheel going uphill.
I think that as long as you have plenty of snow and ice and there is no risk of one wheel suddenly hitting dry pavement, you should be OK. YMMV

 

[TJBaker57]

Right about 1:31 in this clip is heard the sound you don't want to hear...

 

[littleblazer]

Right about 1:31 in this clip is heard the sound you don't want to hear...

That's what the brand new one in my colorado sounds like everytime it kicks in inside the truck. Scares me every time... I wish I could've ordered it with the dual electronic lockers instead because it makes the boat ramp interesting. That was a 2020 and up option sadly.

 

[TequilaWarrior]

Right about 1:31 in this clip is heard the sound you don't want to hear...

I wouldn't say it "grenaded".... but that "ptink" noise is what it sounds like when the diff spits a few teeth out the diff cover...

 

[Mektek]

It seems that the g80 can be made fairly bulletproof. Look at these guys drifting:

If their mods make it survive that kind of abuse I wonder if I should do it to my g80. On the other hand, I have no intention of drifting in my TB

 

[TequilaWarrior]

It seems that the g80 can be made fairly bulletproof. Look at these guys drifting:

If their mods make it survive that kind of abuse I wonder if I should do it to my g80. On the other hand, I have no intention of drifting in my TB

I had this exact differential in my 75 GMC K10 1/2 ton... it was an absolute beast.... until it spit one of those small flywheel weights out of the diff cover, taking 3 ring gear teeth with it... at 80 MPH on dry roads with no loss of traction. There are better ways to keep your gov-lock from going boom that involve ensuring the weights don't fly off. As for disabling the disengagement feature, that's really a niche application. It's not highly desirable to have full lock when the ring gear is at high RPM and when it is, a spool is probably the best solution. If you insist on "road manners", then an air locker is a good choice. Now, if you'll excuse me, I have to go take a xanax and lay down after watching him weld.

 

[Mektek]

Probably what I'll do is slightly reduce the size of disengagement weight so it will unlock at a bit higher speed. No welding needed - just a slight snip.

 

[TequilaWarrior]

Probably what I'll do is slightly reduce the size of disengagement weight so it will unlock at a bit higher speed. No welding needed - just a slight snip.

That's probably "OK" but please don't grind the weight down while it is installed in the diff.... remove it, make your modifications, clean it properly then reinstall it properly so you can ensure it will not come apart on you while in operation and so you don't contaminate your diff. Also, there are two weights opposite of eachother very similar to how weights are in a distributor. You'd want your weight reduction to be equal between the two to keep things in balance.

When my G80 blew up in my '75 I found the remains of the weight still in the assembly. It broke off fairly cleanly. I would caution you against modifying those weights in any way that compromises their durability as they whirl around and a pretty high speed.

It may be worth while investigating whether replacement springs are available for making this sort of adjustment instead of modifying the weight - would give more predictable results.