No Posi-Traction?

[Artsyguy]

I've noticed my 2015 Chevy Express 2500 seems to only spin one wheel (Driver side).  Is it possible that is the ONLY driven wheel?  Winter might be a bit tough with a steep driveway.  I've already had to back up a couple of times to get traction on DRY surfaces!   Has anyone done a conversion or know if it's possible to get both rear's to drive?
Thanks!

 

[Ballenxj]

I've noticed my 2015 Chevy Express 2500 seems to only spin one wheel (Driver side).  Is it possible that is the ONLY driven wheel?  Winter might be a bit tough with a steep driveway.  I've already had to back up a couple of times to get traction on DRY surfaces!   Has anyone done a conversion or know if it's possible to get both rear's to drive?
Thanks!

I would have to say yes. I took my Dodge to a differential shop, and later that day rolled out with a Detroit Tru-Trac installed. $900.
I know there are plenty of options out there for Chevrolet too. Had an Auburn limited slip installed in my old El Camino.
First thing you have to do is find out what differential yours has, then find out what options are available for it.

 

[highdesertranger]

what he said^. also I would like to point out that is not your only driven wheel. an open axle sends the power to the wheel with the least traction, could be right hand wheel could be the left. could go back and forth between both. if both wheels have equal traction then both wheel will be driven. highdesertranger

 

[Ballenxj]

what he said^.  also I would like to point out that is not your only driven wheel.  an open axle sends the power to the wheel with the least traction, could be right hand wheel could be the left.  could go back and forth between both.  if both wheels have equal traction then both wheel will be driven.  highdesertranger

And a trick that was pointed out to me in my old thread (I think?) about basically the same thing was to lightly apply the emergency brake, which will in theory, apply equal traction to both wheels. Kind of a poor mans posi. I never used that method, opting for actual posi instead. Worth a try if you are stuck though?

 

[TMG51]

I would have to say yes. I took my Dodge to a differential shop, and later that day rolled out with a Detroit Tru-Trac installed. $900.
I know there are plenty of options out there for Chevrolet too. Had an Auburn limited slip installed in my old El Camino.
First thing you have to do is find out what differential yours has, then find out what options are available for it.

I want to get this done, but I'm not sure I have any "differential shop" options around here. What sorts of shops should I call around at?

 

[Ballenxj]

I want to get this done, but I'm not sure I have any "differential shop" options around here. What sorts of shops should I call around at?

The name of the shop I used is "Idaho Gear." Some shops do both differentials and drive lines. What area are you looking for this shop in? You can enter the location and query into both google and yelp to see what comes up. If you're driving down the road and see a nice Hot Rod, you might ask the owner who he or she would recommend. Hot Rodders should surely know.

 

[highdesertranger]

the 4x4 crowd knows were to get it done. I know of some shops in So Cal. highdesertranger

 

[Ballenxj]

the 4x4 crowd knows were to get it done.  

Yes they should as well.

 

[Artsyguy]

Thanks for the clarification. It doesn't seem like both my wheels are driving, but I guess I could put it up on a lift, press the gas, and both should spin...If not, then we've got a problem.

 

[highdesertranger]

no you don't have a problem. one might spin or both might spin. that will tell you nothing. there are a couple of ways to check but I am hesitant to tell you as they could be dangerous. you have described nothing out of the ordinary. highdesertranger

 

[Ballenxj]

  It doesn't seem like both my wheels are driving, but I guess I could put it up on a lift, press the gas, and both should spin...If not, then we've got a problem.

No need to have the van's engine running. Lift the two rear wheels off the ground and make sure the van is safely blocked so it cannot fall. Next, put the gear selector in neutral and make sure the parking brake is not engaged.
Now spin one of the rear wheels. If the wheel on the other side spins in the opposite direction or not at all, you have an open rear. (no posi)
On the other hand, if they both spin in the same direction, you have posi.
For clarification, posi is short for positraction, limited slip, locker, etc.

 

[TMG51]

No need to have the van's engine running. Lift the two rear wheels off the ground and make sure the van is safely blocked so it cannot fall. Next, put the gear selector in neutral and make sure the parking brake is not engaged.
Now spin one of the rear wheels. If the wheel on the other side spins in the opposite direction or not at all, you have an open rear. (no posi)
On the other hand, if they both spin in the same direction, you have posi.
For clarification, posi is short for positraction, limited slip, locker, etc.

This is the correct answer, as far as a test is concerned.

 

[steamjam1]

An LSD and a good set of tires.. That's really all you need.

You might want to do some research and find out if your year, make and model of van had LSD's as an option when new. You may be able to go to a wrecker and buy a complete axle for cheap...

 

[Optimistic Paranoid]

An LSD and a good set of tires.. That's really all you need.

You might want to do some research and find out if your year, make and model of van had LSD's as an option when new. You may be able to go to a wrecker and buy a complete axle  for cheap...

I completely agree with the first statement.

As for the second, factory limited slips rely on internal clutches that wear.  By the time it has 80,000 miles or so on it, the limited slip is probably no longer functioning.  A shop COULD open it and rebuild it with new clutches, but the cost might be close to having a Tru-trac put in, which does not use clutches and consequently never wears out.

 

[user 37446]

I completely agree with the first statement.

As for the second, factory limited slips rely on internal clutches that wear.  By the time it has 80,000 miles or so on it, the limited slip is probably no longer functioning.  A shop COULD open it and rebuild it with new clutches, but the cost might be close to having a Tru-trac put in, which does not use clutches and consequently never wears out.

I dont have any experience with your setup other than you could look in the glovebox on the option code sheet and see if you have a "G80", which is GM's posi.

As far as LSD or locking diffs, go on the 4x4 sites for endless discussions. Here's one from a jeep forum:

[font=verdana, arial, sans-serif]Thanks for all the input guys - again, this topic isn't about lunchbox lockers (as we have far too many threads arguing about their benefits and behaviors in various conditions) but rather a selectable locker in the front and a limited slip (TrueTrac) in the rear.[/font]
[font=verdana, arial, sans-serif]On the front locker issue, I'm planning on a selectable locker - no questions asked. Ideally electronic for the sake of simplicity (as sunburned has described).[/font]
[font=verdana, arial, sans-serif]In the rear, my only reasoning for a TrueTrac is as follows:[/font]
[font=verdana, arial, sans-serif]I do enjoy high-speed fun in 2WD on dirt/gravel roads on private land (think south Texas terrain), and want more predictable behavior in those scenarios. Seems like the TrueTrac is a winner in the LSD arena for multiple reasons (maintenance-free, seemingly pretty beefy) and would fit the bill.[/font]
[font=verdana, arial, sans-serif]In the event that traction is limited in the rear (i.e. one wheel in the air), a locked front in conjunction with part-time 4WD would likely be sufficient to get me moving again in just about every situation I've ever been in. I don't rock crawl, so these scenarios are pretty few and far between.[/font]

 

[UptownSport]

One issue is less stability on slick surfaces- especially side hills. With an open differential, the non spinning tire tends to keep the vehicle from sliding sideways- to fishtail. It was more apparent on RWD than FWD. Not at all to make this a ‘You will die’ post.

Desired effect- in most applications, is far less than you'd hope. I guess when you're stuck, you're stuck. A set of chains would be far, far better than a LSD.

Installation is pretty straightforward, you need a dial inch lb torque wrench, dial indicator, and shims. With Dana Spicer axles, you need a special spreader.

I installed few RWD, but many FWD for special application.

As mentioned, there's many, many different types. I have a Torsen style now, and really like it. The simplest is what we called the Ford ‘S-spring'. You'd laugh.

Overall, they're fun to talk about, but I'd never install one for a dd, or suggest the average person install one. There just isn't that much difference in most situations.

 

[user 15722]

Difficult to compete with a bold presentation but I have seen many fellows proud of their posi get stuck worse than others.
Locked front & rear does work.
I generally prefer a nice hi-way tread tire for best mileage with snow chains for traction issues.
Chains are superior traction in mixed dirt/rock/sand than almost any roadable tire made.
The sand rail paddle tires for that specific purpose will move a lot of sand ! lol wheels