Locker or Limited Slip?

[sprpilot]

Getting tired of spinning A wheel on slipery roads instead of ALL wheels. Got a 2001 2500 4x4 5.9. Looking to get some sort of traction device installed this fall. Who has what on their rig, and what do you recommend? Not looking to go rock crawling, just everyday driving, and pulling a trailer in the winter.

Edited July 18, 2018 by sprpilot
Added more exsplanation

[dripley]

Mine is LS and dont have any problems with it. Drives well in the mud I drive it in on the job and does well in the winter with snow with the tires I have on it. Not alot of off road stuff for me though.

[Haggar]

Your existing rear differential could be a limited slip.  Most likely the clutches are just worn.  Just replacing those and a re-stack (depending on which axle you have) should bring the rear axle back into mostly positive traction.  (automatic 2500's got the dana 70u and manual trucks got the dana 80.  not enough information in your signature or description to tell which you have.)   If no one has lost it, there should be a tag under a diff cover bolt telling you to add limited slip additive.

 

The front axle has a couple different possibilities with different pros  and cons associated to each method.    Air locking is the best of all worlds, just very spendy. 

 

Are you sure your front axle is working?  Reason I ask, I will spin in wet grass in 2wd.  When I put her in 4 I never have been stuck. (knocks on wood) (I have vultures circling, just waiting to hook me to the sucker end of a tow strap!)  I don't have the snow and such you have, but when we do, the weight on the front axle is all I have needed so far even though the front diff is open.

 

HTH

 

Hag

Edited July 18, 2018 by Haggar
added knock on head or closest wooden object

[trreed]

For every day driving, it's hard to beat a Dana Trac-Lok (factory unit).  Easy to pull apart and restack clutches as mentioned above.  In a perfect world, I'd like to find an Eaton TrueTrac unit because it's a helical design so no clutches to wear out.

[sprpilot]

3 hours ago, Haggar said:

Your existing rear differential could be a limited slip.  Most likely the clutches are just worn.  Just replacing those and a re-stack (depending on which axle you have) should bring the rear axle back into mostly positive traction.  (automatic 2500's got the dana 70u and manual trucks got the dana 80.  not enough information in your signature or description to tell which you have.)   If no one has lost it, there should be a tag under a diff cover bolt telling you to add limited slip additive.

 

The front axle has a couple different possibilities with different pros  and cons associated to each method.    Air locking is the best of all worlds, just very spendy. 

 

Are you sure your front axle is working?  Reason I ask, I will spin in wet grass in 2wd.  When I put her in 4 I never have been stuck. (knocks on wood) (I have vultures circling, just waiting to hook me to the sucker end of a tow strap!)  I don't have the snow and such you have, but when we do, the weight on the front axle is all I have needed so far even though the front diff is open.

 

HTH

 

Hag

No tag. I bought the truck with after market Diff. covers. This last winter I was trying to go up a road on 2 in. of fresh snow, not realizing that it was solid ice underneath. I chained up both rear tires and started on, but only one tire turned, and it broke my tires chain due to ALL the torque being exerted on only one instead of both. There is sometime dirt along the edge of the road I could use for traction, but not when the one with the LEAST traction is the only one that turns.

3 hours ago, trreed said:

For every day driving, it's hard to beat a Dana Trac-Lok (factory unit).  Easy to pull apart and restack clutches as mentioned above.  In a perfect world, I'd like to find an Eaton TrueTrac unit because it's a helical design so no clutches to wear out.

I agree, but from the research I have done the Eaton does not fit what I have due to different number of splines on the axle I have, and what they have to offer.

[Haggar]

I am not near my truck.  IIRC  the code for limited slip was DSA.  I am not seeing that on your sheet.

 

I am seeing everything in the world  for spline count. (except the 37 lol)  So far, I think the 70-2U was 32 spline, but so many people dump all the 70's in one lump or only the 70b and 70u....   But a nice write up on pirate 4x4 on the dana leads me this way.

I cannot confirm the count through the factory parts list. The part number for the 70-2u axle is 0474662.   I can only find stock descriptions for that part.... 

 While the eaton power lock is not available apparently in the 32,  new axle shafts are only about 200 each in chrome moly (less in regular alloy (one possibility).   The other possibility is detroit lockers and dana units are available brand new in many more spline configurations. 

 

It looks like you have a totally open carrier right now, so any of the above ideas are a killer step forward. 

 

GL  HTH

 

Hag

 

[Mopar1973Man]

1 hour ago, sprpilot said:

This last winter I was trying to go up a road on 2 in. of fresh snow, not realizing that it was solid ice underneath. I chained up both rear tires and started on, but only one tire turned, and it broke my tires chain due to ALL the torque being exerted on only one instead of both.

 

Wow. In all the years out here in New Meadows, ID I've only chained up ONCE. Just to see if the chain fit good. Since then I've travel most all the local roads in 2WD. Very, Very rare for me to grab the 4WD and use it in the winter. To this day I still pack my chains in the truck and my tow chain but never used them in over 349k miles of road being traveled. My secret weapon is the 235's I typically run since I switched from the 265's to the 235's I've always had good winter traction without the need for chains. 

 

 

[sprpilot]

Try pulling a snowmobile trailer up a narrow mountain road with solid ice under 2 in. of snow. I opened my door got out and promptly fell on my ***. You could hardly walk at all it was so slick.

[Mopar1973Man]

Yeah. Many days of that. Again the trick is more weight per square inch gains better traction. So in just reducing my footprint by dropping tire size help a bunch. 

 

I've been to several fire calls (vehicle accidents) where I got out and fell on the highway and fought to even stand up. I've also travel up many snow covered forestry roads in the dead of winter hauling a snowmobile trailer in the past. (Sold the sled). Still have to travel these roads to visit friends. 

 

Simple way to look at it. If you to walk out in deep snow you'll sink with every step. Now if you put on snowshoes now you can walk across the top of the snow. Wider footprint allows you to spread your weight over more square inches allowing you to float on top. This is why I held to the 235's for so long because with 4,400 pounds on the front axle narrow footprint gave me way better bite on ice. Now with my plans to switch 245's footprint is going to change again as well being almost a inch wider. Tread face does matter too. M/T tires tend to perform rather poorly. Like my last two sets of A/T's (Hankook) ran wonderfully on snow, ice and slush still to this day no chains. 

 

Oh I almost forget to say... Its a Open Diff Dana 80. No limited slip at all.

Edited July 18, 2018 by Mopar1973Man

[sprpilot]

I totally agree on the tire size point. That is why I use skinny high profile tires in the winter instead of "Jumbo Mudders". I have a little wider lower profile tires on separate rims for summer highway driving.

[Dieselfuture]

7 hours ago, trreed said:

For every day driving, it's hard to beat a Dana Trac-Lok (factory unit).  Easy to pull apart and restack clutches as mentioned above.  In a perfect world, I'd like to find an Eaton TrueTrac unit because it's a helical design so no clutches to wear out.

I heard that they wear out too, but not sure how. I held one in my hands trying to figure out how it works lol

[trreed]

Not the greatest explanation, but shows how the moving parts interact.

Operates on the principle of gear separation.  Basically the helical gears mesh harder into each other when the side gears have a difference in speeds, even down to stopping the wheel that has little traction to equalize the load.

Edited July 18, 2018 by trreed

[Mopar1973Man]

24 minutes ago, sprpilot said:

I totally agree on the tire size point. That is why I use skinny high profile tires in the winter instead of "Jumbo Mudders". I have a little wider lower profile tires on separate rims for summer highway driving.

 

Beyond that, you would need to adjust your tire pressure based on the axle weight of the current time. Like myself I typically do the pressure math and round down or subtract about 5 PSI on the pressures allowing the tires to be a bit soft sided and conform to ice better. Then in the summertime I do the same math and round up or add about +5 PSI.

 

 

 

[sprpilot]

Great video. Now if they just put one out for the 32 spline I would get it tomorrow.

 

[trreed]

There is is!  Right out of Eaton's catalog

[sprpilot]

Sweet!! I will go check it out. Thanks.

[trreed]

Compatibility charts state this is compatible with D70's found in 2nd gen pickups, but there is never a spelled out sentence where it states it is for a 70U

[sprpilot]

Can you post the link?

 

[sprpilot]

So I checked out the 225SL107D part number and it say it is a Detroit Locker type by Eaton. Check out this video. I want the Torsen True Track type. Might have to wait.

 

https://www.drivetrainshop.com/Detroit_Locker_p/eat-225sl107d.htm

 

[AH64ID]

The Tru-Trac is what you want. I wouldn't ever spend another penny on a clutch style LSD, as they are about worthless in my book (and I've ran more than one, in more than one truck, and spent too many pennies on them). 

 

The helical gear style LSD is the best working LSD with it's only drawback is that it doesn't work as well from a dead stop but as soon as there is a little wheel movement it's better. I now have more miles on a helical gear LSD than a clutch style and will never go back. The OEM LSD in 03+ is a helical gear style. 

 

In my experience clutch pack LSD's will "lock" when you don't want them to, such as on ice, and won't do crap when you want them to, such as deeper snow, mud, loose dirt, wet pavement, etc. Nothing like a clutch pack LSD causing the back axle to walk on off camber icey section of a USFS road! That will make you pucker!!! Done the same stretch of road hundreds of times with a clutch-style and a helical gear style and the helical gear style has never unexpectedly walked on me. 

 

Other things to do are to ensure you have the proper air pressure for the load, and good tires. 

 

I've had to chain up quite a few times but it's always been warranted, such as breaking trail in 18"+ of snow or solid ice on off camber roads. I'd much rather chain up for a few miles than wish I had when I'm into a ditch or tree. These are good trucks, but with the low weight in the rear and lots of torque they can easily be traction challenged, and the leaf spring setup in 1st and 2nd gens makes them even more prone to loss of traction.