"Anti-spin" questions.

[Mkickham]

Hey, I've got a question about the differential in my truck. It's a 2013 SXT, rwd, with the 5.7, 6 speed auto, and 3.55's. I got the truck new in April 2013, and it was built for me, because nobody else wants rwd. I ordered it with the anti spin differential, and that's listed on the build sheet. The brakes started to squeal a bit lately, so yesterday I took them apart to do a brake service (remove the rust ridge, chamfer the pads, etc). When I had the rear jacked up, I tried to spin a rear wheel, expecting it to lock. I was very surprised when the other rear tire spun the other way, with the truck in park, as it would in an open differential. My question is, can this be an anti spin axle? I know how they usually work, as I've rebuilt many before. I just don't know if there is a mechanical locker that triggers at a certain rpm difference between the tires, or if it should still be the old style with the stack of friction disks? Does anyone know what type this truck should have? I strongly suspect the wrong axle may have been installed on my truck, as to my knowledge gm is the only one to use an actual locker. Thanks in advance!

 

[Ricks Ram]

No they still use a clutch style carier in our trucks. For some reason Chrysler seems to set them up pretty lose. My truck has the Anti-spin with 3:92's and when I jack it up it does the same thing. I thought the same thing you did. Also my truck does not have a Tag on the rear end for limited slip lube so I thought for sure they put the wrong differential in my truck. If you pull the fill plug you can see the spider gears with no clutches between them which would tell you it's an open differential but it is not. Chrysler actually uses a small clutch pack on both sides of the carrier one clutch pack for each axle. You can't see them unless you actualy pull the cover off of the differential. That being said I did have to have mine replaced under warranty because the drivers side clutches wouldn't activate for some reason. It was a battle to get them to admit it didn't work right. Any diff will spin both tires together if the have equal traction. The best way to check and see if yours is working right us to pull off the road and get one tire in the grass and one on the pavement hit it and see if both tires spin you should hear the tire on the pavement spinning then do the other side it should do the same. Mine works now but they realy aren't that great in a true situation that you might need them but still better than an open.

 

[AzRamLover]

Very, very few limited slip/anti-spin (non-locking) differentials are capable of handling the situation you describe.

LSDs have a torque bias ratio - usually something like 3:, 4:, or even 5:1. That means that they can split torque 75/25, 80/20, or even 85/15. The key thing to understand is that they do require *some* grip on the other tire in order to work their magic.

So if you were to lift one tire completely off the ground and leave the other on the ground, the LSD will act basically like an open diff.

Solutions:

1) Locking differentials (lots of these variations)
2) Wavetrac LSDs (they're pricey but they do work even if one wheel is completely in the air; I don't think they make one for our trucks)
3) Torque vectoring LSDs w/ sophisticated electronics/sensors

 

[Ricks Ram]

They don't make any aftermarket differentials for the late 4th gen yet that I have been able to find or I would have already changed out the stock LSD. I understand how limited slip differentials work and some are able to transfer more torque than others. Also some L.S.D differentials do spin both tires in the same direction when they are of the ground. But most of the newer ones do not. In my case one of the things the technician did when I had them drive my truck was exactly what I described and it would only work on one side. It didn't trasfer any torque at all on the other. It acted completely like an open differential. My truck easily spins both tires in the situation I described since I have had it replaced.

 

[Tach_tech]

That's normal for the new LSD setup they are using, it's not like the older ones you are probably used to. It actually needs torque applied to the gear set to operate.

 

[bubbasneed]

They don't make any aftermarket differentials for the late 4th gen yet that I have been able to find or I would have already changed out the stock LSD.

Auburn makes one, it is part number 5421042.

My truck has the open diff and I just ordered a limited slip from Matt at Moes performance and he suggested the factory one over the Auburn one though. The Auburn unit is more expensive and he sold both units (doesn't have the Auburn on his website) and he said if I was looking for more traction then get the Mopar unit, if my goal was to do donuts then get the Auburn unit.

I ordered the Mopar unit based on his recommendation. I just hope it is worth the $650-$700 everything is going to cost me. I probably would have been fine with the open diff since my Ram is 4X4.

 

[Ricks Ram]

Your right I think I did talk to a shop that said that Auburn made one for our trucks. I stand corrected on that. I forgot. He said the same thing that Moe's told you its really not much of an upgrade from the stock unit if any. My differential works fine since I had it replaced. It was definetly defective.

 

[fasthemiram12]

You can put the DTT in a ZF axle.
It just takes extra know how. I have one in my 12

 

[Hemifatboy]

For those that don't know , if you get into a spot where only one wheel will spin because of no traction at all , you can apply a small amount of brake to get posi to work , it may sound crazy but it works

 

[clh1220]

Auburn makes one, it is part number 5421042.

My truck has the open diff and I just ordered a limited slip from Matt at Moes performance and he suggested the factory one over the Auburn one though. The Auburn unit is more expensive and he sold both units (doesn't have the Auburn on his website) and he said if I was looking for more traction then get the Mopar unit, if my goal was to do donuts then get the Auburn unit.

I ordered the Mopar unit based on his recommendation. I just hope it is worth the $650-$700 everything is going to cost me. I probably would have been fine with the open diff since my Ram is 4X4.

I was waiting to see how mine did in the snow. And it did fine with auto 4wd, and traction control that I decided not to get lsd installed. I it pulls the boat up the ramp in 2wd no problem.

 

[RLJ10X]

I'm pretty sure these trucks do the "Brake Lock" thing, if the traction control is on. No longer any need to apply brake yourself.

These LSD rear ends are not what most of us are used to. They're probably put together the way they are because it's safer, and will keep Dodge from being sued. They are not a Posi Trac. However, they do pretty well. Defiantly better than an open.

 

[bubbasneed]

I was waiting to see how mine did in the snow. And it did fine with auto 4wd, and traction control that I decided not to get lsd installed. I it pulls the boat up the ramp in 2wd no problem.

Hey that is good to know. If I would have read this before I bought all of my stuff I would have probably have waited. I am just waiting now for the install to be done which might be today.

Thanks

 

[bubbasneed]

Your right I think I did talk to a shop that said that Auburn made one for our trucks. I stand corrected on that. I forgot. He said the same thing that Moe's told you its really not much of an upgrade from the stock unit if any. My differential works fine since I had it replaced. It was definetly defective.

Hey Ricks Ram I wasn't trying to correct you, just wanted you to know that there is an aftermarket lsd out there even if it doesn't seem to be much of an upgrade.

Cheers

 

[Ricks Ram]

Hey Ricks Ram I wasn't trying to correct you, just wanted you to know that there is an aftermarket lsd out there even if it doesn't seem to be much of an upgrade.

Cheers

No offense taken. You were right I forgot about the auburn.I was looking around for exactly the same reason everyone is talking about. These new L.S.D. differentials leave a lot to be desired compared to to older units from the past. They aren't nearly as good in off road situations where you have drastic traction differences in either axle but they do help some. If the traction is closer to the same on both wheels they work great. They are still better than an open differential.

 

[Shambo]

I just replaced my open diff with a ZF limited slip from Moes! Haven't been is a situation yet to see the difference, I guess I just need to go to the track!

 

[CrownHill]

Hey everyone, it's really good reading what everyone has to say about the parts availability, it gives me some hope. I accidentally got stuck with the 3.21 (2015 sport) and open diff, I actually have had it open because one of my wheel lug nut studs was damaged from the factory and in order to change it you have to pull the axle out of the diff to leave room for clearance of the stud (I have pictures). Anyway no lsd and the 3.21 is a really horrible setup and I want to change this, do I have to change the front diff as well when I change the sizes?

 

[quietpeen]

Hey everyone, it's really good reading what everyone has to say about the parts availability, it gives me some hope. I accidentally got stuck with the 3.21 (2015 sport) and open diff, I actually have had it open because one of my wheel lug nut studs was damaged from the factory and in order to change it you have to pull the axle out of the diff to leave room for clearance of the stud (I have pictures). Anyway no lsd and the 3.21 is a really horrible setup and I want to change this, do I have to change the front diff as well when I change the sizes?

Yes you have to change the front, or never use 4wheel drive again

 

[CrownHill]

Ah ok thanks going to have to look into the parts needed, if anyone has any tips or advice throw it in because I'm going at this with my mechanic/friend and we both lack info on the subject, probably going to go with the 4.10. I'll be contributing many pictures and anything new I learn that I can share.

 

[clh1220]

Ah ok thanks going to have to look into the parts needed, if anyone has any tips or advice throw it in because I'm going at this with my mechanic/friend and we both lack info on the subject, probably going to go with the 4.10. I'll be contributing many pictures and anything new I learn that I can share.

Your going to spend more money than it's worth. With it being 4wd. That front diff is going to be high dollar. Installing gears in the rear needs to be done by somebody that really knows what he is doing.

 

[RLJ10X]

Well, I'm stuck with the 545RFE. I had the 3.55 open.

Since the 4.10s, Anti Spin, and Hemi Fever, I'm pretty happy with the truck. <If it wasn't for those 3 things, I'd have a different truck by now.

Crown, call Matt at Moe's. He's a site sponsor. He has all your answers. If possible, you'll really like 4.10s. Those gears should have been standard. 70mph at 2000rpm in my truck. Hasn't hurt gas mileage on bit in my case. See mods listed below.