Chevy Express Rear Differential Info

[akrvbob]

Thanks. Since I'm not a Jeep trails or snow-plowing kind of guy, the locker options would be overkill for me, and I wouldn't want to deal with upkeep on a LSD. If the military uses Torsens then that's enough of a recommendation for me. No special servicing, no buttons or levers to use, no clunking... Now I just need to come up with the money.

Too bad you don't know anyone who would pay you to do something you really enjoy doing!!  

 

[MrNoodly]

Too bad you don't know anyone who would pay you to do something you really enjoy doing!!  

Maybe this winter, after I get a more powerful laptop.

 

[Ballenxj]

The Detroit TruTrac is a limited slip that doesn't use clutches and never wears out.

That's why I put one in my Dodge 9 & 1/4 Dodge diff, but you guys don't want to hear about that here.  
 After much research I determined that was the pick of the litter for limited slips. Goes by both Detroit and Eaton names.

 

[hangtownmatt]

I'm not sure if I've been proven wrong, but my original post which started this thread was a heads-up that the Eaton (also called Detroit) Tru Trac is not available for late model Chevy Express vans. This, to me, is significant because I believe the Eaton Tru Trac LSD is the best solution for conservative off road adventure in these vans. Significant enough that I did not buy one. The source of this bad news, for the record, was West Coast Differentials. I'm clarifying because I originally referred to the Tru Trac as a locker, which I think it is, but technically should probably be referred to as a LSD.

Matt

 

[gapper2]

Matt,
  I don't think you have been proven wrong about anything.  The different manufacturers use all this terminology very loosely.  You were wanting a tru trac.  Not available.  As Dave06 mentioned the new trucks come with an option package that is promoted by gm as a HD locking differential.  But if this is the G80 option, It is only a limited slip because it still has clutch packs and uses fancy flyweights and counter weights to change the diff from full open to locked with no operator intervention.  I wouldn't think this would be a non-maintenance needed item. Depending how you drive I guess. Probably good enough for most of us.

Thanks for bringing this thread up.  I've learned lots more on the subject even though hopefully my vehicle will be my last and I've got mine.

 

[hangtownmatt]

gapper2,

It certainly is confusing. The way I understand it is, and again I could be wrong, is:

- A LSD transfers the power from the slipping wheel to the other, but both wheels do not have power at the same time.
- A locker sends power to both wheels simultaneously.

I believe that is why GM refers to the G80 as a locker and not a LSD.

Matt

 

[Optimistic Paranoid]

gapper2,

It certainly is confusing.  The way I understand it is, and again I could be wrong, is:

-  A LSD transfers the power from the slipping wheel to the other, but both wheels do not have power at the same time.
-  A locker sends power to both wheels simultaneously.

Uhm.  Not exactly right, I'm afraid.

A regular differential, called an "open diff", will send 100% of the power to a spinning wheel and zero power to a non-spinning wheel.

A limited slip differential will see to it that SOME of the power will continue to go to the non-spinning wheel.  However, depending on the weight of the vehicle, the degree of slope you might be trying to climb, etc. the percentage sent to the non-spinning wheel may not actually be enough to keep the vehicle moving.

A locked differential always sends equal power to both wheels.  Both wheels will turn at exactly the same rpm at all times.

 

[tx2sturgis]

A locked differential always sends equal power to both wheels.  Both wheels will turn at exactly the same rpm at all times.

Which is EXACTLY why some 4 wheelers get high centered in the quicksand/mud/muck/river juice.

All 4 driving wheels (or the only 2 drive wheels) spinning in the soft stuff means you get to prove that gravity works!

In my own humble opinion: If you install a locker, then by all means, spend the money to install some type of winch, or at least bring along some T-posts, a hi-lift jack, a come-along/power puller and a shovel. Over-confidence in your drive system, and under-analysis of the conditions, leads you 50 feet further down the trail when you DO get stuck!

You will thank me sooner or later!

 

[MrNoodly]

Here's the best explanation I've found of a Torsen diff.

 

[Ballenxj]

I'm not sure if I've been proven wrong, but my original post which started this thread was a heads-up that the Eaton (also called Detroit) Tru Trac is not available for late model Chevy Express vans.  
<-------->
 I'm clarifying because I originally referred to the Tru Trac as a locker, which I think it is, but technically should probably be referred to as a LSD.

The Tru-Trac has very limited slip, and is achieved with the use of worm gears as opposed to clutches, therefore no maintenance required, and no burned out clutches to replace.
I did a lot of research before settling on mine. Also referred to as a Torsen type differential.
One that you might consider is made by Auburn Gear. It is capable of handling around 400 HP, and is neat the way it works. The more throttle you throw at it, the tighter it locks up, but if you're easing around a turn, it allows more slippage. It works on torque. I had that system in my El Camino, and was happy with it.

 

[Ballenxj]

Auburn Gear. http://www.auburngear.com/

 

[Optimistic Paranoid]

In my own humble opinion: If you install a locker, then by all means, spend the money to install some type of winch, or at least bring along some T-posts, a hi-lift jack, a come-along/power puller and a shovel.

I used a come-along - ONCE! - to get our tractor unstuck down in the bottom pasture.  I would rob liquor stores to pay for a winch before I would ever again rely on a come-along for getting unstuck!

 

[tx2sturgis]

I used a come-along - ONCE! - to get our tractor unstuck down in the bottom pasture.  I would rob liquor stores to pay for a winch before I would ever again rely on a come-along for getting unstuck!

Oh they are a pain to use...but sometimes being cheap means $50 instead of $500...

And a tractor? What WERE you thinking?

I have seen 80,000 pound snatch straps that couldn't budge a stuck tractor...

 

[hangtownmatt]

In my own humble opinion: If you install a locker, then by all means, spend the money to install some type of winch, or at least bring along some T-posts, a hi-lift jack, a come-along/power puller and a shovel. Over-confidence in your drive system, and under-analysis of the conditions, leads you 50 feet further down the trail when you DO get stuck!

You will thank me sooner or later!

Not sure how to reply to this comment.

Matt

 

[tx2sturgis]

Not sure how to reply to this comment.

Matt

Matt, the gist of that is:

If you plan to be alone and taking the van down some gnarly trails, muddy washes, soupy river bottoms, or whatever, and you are thinking that the locking rear diff can get you unstuck...it probably wont. So it might be a good idea to have a back-up plan.

If you drive it on normal dirt roads and occasional rough but dry two-tracks, then you will probably be ok.

 

[hangtownmatt]

Matt, the gist of that is:

If you plan to be alone and taking the van down some gnarly trails, muddy washes, soupy river bottoms, or whatever, and you are thinking that the locking rear diff can get you unstuck...it probably wont. So it might be a good idea to have a back-up plan.

If you drive it on normal dirt roads and occasional rough but dry two-tracks, then you will probably be ok.

To clarify, I think most of us are simply trying to find a solution to the Chevy Express's open differential that can leave us stuck on flat ground.  There aren't many options.  Being able to go down a forest service road with some level of confidence is a bonus.  Being able to meet grandma on Christmas with a little ice on the ground is a bonus.  After all, traveling is a big part of why I'm getting into this lifestyle.  IMO, if the ability to lock both rear wheels is needed only once it's paid for itself.  And having it doesn't mean I'm now going to just get suck 50 yds further down the trail.  Installing a locker does not mean a person lacks common sense.

Most of my off road experience comes from owning and operating a 4x4 tractor in the California foothills.  I could lose traction on dry weeds in the middle of summer going up a slight incline.  Sometimes 4wd would get me moving again, but not always.  However, if I locked the rear differential I was able to get out of any situation I got myself into; summer or winter.

Again, having these tools doesn't mean we lack common sense.  I'm pretty sure you did not intend it this way but some of your posts come across that way.

Matt

 

[tx2sturgis]

Again, having these tools doesn't mean we lack common sense.  I'm pretty sure you did not intend it this way but some of your posts come across that way.

Matt, in any of these forums, there might be 100, or 1000, or 10,000 people reading them. If my posts are in anyway mildly offending you, they may be helping a hundred others who come by later and read this stuff.

Some of the members may find the information valid, even if it's perceived by you as slightly 'dumbed down'. For that I apologize. But I have no inkling of your level of experience or competence.

I myself have made errors when 4-wheeling...and had to be pulled out. But that's part of the fun and I always had others in the area to assist me if needed.

No offense was intended. I hope you find your solution.

_____<<<< cheers smiley goes here.

 

[MrNoodly]

If you drive it on normal dirt roads and occasional rough but dry two-tracks, then you will probably be ok.

That has worked for me -- so far -- with an open diff. That's why I haven't rushed to get something else .

 

[Optimistic Paranoid]

And a tractor? What WERE you thinking?

Actually, it was my father who got his tractor stuck.

At which point my assistance was NOT considered optional . . .

But we should probably stop drifting off topic.

 

[akrvbob]

In my own humble opinion: If you install a locker, then by all means, spend the money to install some type of winch, or at least bring along some T-posts, a hi-lift jack, a come-along/power puller and a shovel. Over-confidence in your drive system, and under-analysis of the conditions, leads you 50 feet further down the trail when you DO get stuck!

I very much disagree with this idea. I consider locker to be a great idea for anyone who wants to get a little further back--and out again. 

By far the majority of 4x4 folks I've known agree that a locker is a great choice for a van.

(YES, I edited my typo!!  )