A Limmited Slip Differential Question

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Tanker

Tanker

My first Chrysler
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This question isn't about my Duster, it has to do with my 1998 Dodge Ram 2500. As I've always understood it, with one of these differentials the power is supposed to transfer to the wheel with better traction. My question is, how quickly should that happen? My driveway is fairly steep. At the top by the garage there's room for two vehicles side by side, but the actual driveway is only about one and a half full size cars wide. Several times now when coming up the driveway my truck has become stuck when the right rear tire left the pavement and got on the grass while going around another car. When this happens only the right rear wheel spins. The wheel on the pavement just sits there. This is exactly how a standard rear end behaves. What gives? I ordered this truck from the factory and paid for a limited slip differential. When I run the vin code it says I have one, but it sure doesn't act like it, at least not the way I always thought it would. Am I expecting too much? Does it take more time for the power to transfer to the left wheel than I am giving it? It's a Dana 80 rear axle. Any thoughts?
 
Tanker said:
This question isn't about my Duster, it has to do with my 1998 Dodge Ram 2500. As I've always understood it, with one of these differentials the power is supposed to transfer to the wheel with better traction. My question is, how quickly should that happen? My driveway is fairly steep. At the top by the garage there's room for two vehicles side by side, but the actual driveway is only about one and a half full size cars wide. Several times now when coming up the driveway my truck has become stuck when the right rear tire left the pavement and got on the grass while going around another car. When this happens only the right rear wheel spins. The wheel on the pavement just sits there. This is exactly how a standard rear end behaves. What gives? I ordered this truck from the factory and paid for a limited slip differential. When I run the vin code it says I have one, but it sure doesn't act like it, at least not the way I always thought it would. Am I expecting too much? Does it take more time for the power to transfer to the left wheel than I am giving it? It's a Dana 80 rear axle. Any thoughts?
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Outta my league, but is it 4wd? Can ya creep up the hill? I Have had several trucks that were supposed to act as expected, and it the same crap. Tire w/ less traction spins...
 
Jack up one tire, put it in neutral, front tires safely blocked and parking brake released. See if you can turn the jacked tire, and how hard is it. If it turns easily, either it's not limited slip, or it's completely broken. If you can turn it "with some effort" it's limited slip but may not be very good shape. On my old 70 RR 440-6, 3.54 Dana 60 there was NO WAY IN HELL you could slip a tire like I just described.

Also "in reality" clutch type limited slip does not really work as some of the flowery descriptions. REALLY what they do, is when power is applied, the wedges in there engage the clutches tightly, and they really just sort of lock the two axles together until power is relaxed some.
 
My Coronet was the same way. Not moving the wheels. . Heck, we pooped one off Memorial Hgwy, in Tampa, back in the early 90s.. 2 L
Lanes, on a Sunday. A State Trooper rolled by, w/ his Wife (i assume), and slowed way down, using the " push w/ both hands" hand signal... I laughed at him, and my Bro just shook his head at the guy. He didn't come back. That was on ol Mickey Sportsman "i"s..
 
I recently read that some newer Dodge trucks require that the emergency brake must be applied before the sure grip will work. Sounds lame to me. I'm not familiar with this. Check your owner's manual.
 
Tanker said:
This question isn't about my Duster, it has to do with my 1998 Dodge Ram 2500. As I've always understood it, with one of these differentials the power is supposed to transfer to the wheel with better traction. My question is, how quickly should that happen? My driveway is fairly steep. At the top by the garage there's room for two vehicles side by side, but the actual driveway is only about one and a half full size cars wide. Several times now when coming up the driveway my truck has become stuck when the right rear tire left the pavement and got on the grass while going around another car. When this happens only the right rear wheel spins. The wheel on the pavement just sits there. This is exactly how a standard rear end behaves. What gives? I ordered this truck from the factory and paid for a limited slip differential. When I run the vin code it says I have one, but it sure doesn't act like it, at least not the way I always thought it would. Am I expecting too much? Does it take more time for the power to transfer to the left wheel than I am giving it? It's a Dana 80 rear axle. Any thoughts?
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The limited slip function is malfunctioning, because the clutches are burned up from allowing one wheel to spin while the other is at rest. They can stand it some, but doing it over and over and over again, like dropping off the pavement coming up your driveway wore it out. It's time to rebuild or replace it.
 
Don't know about the 1998, but in a 2003 the limited slip differential is complety different, then the clutch or cone types in the early vehicles. I had the back cover off one a few years ago, but can't remember the details. If I am not mistaken, after one wheel turns a certain amount, something like a ratchet assembly locks up. Like I say I could be wrong, but they are different.
 
RustyRatRod said:
The limited slip function is malfunctioning, because the clutches are burned up from allowing one wheel to spin while the other is at rest. They can stand it some, but doing it over and over and over again, like dropping off the pavement coming up your driveway wore it out. It's time to rebuild or replace it.
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I've only lived in this house since 2017 and the truck remains parked all winter. I've had to drive around another car to park up by the garage a total of three times, and each time it got stuck. Prior to that the truck was only driven on the streets of Los Angeles, so while burned up clutches as you describe may very well be causing the problem, I'd be surprised if it happened here in Pittsburgh. But this brings up another thought. The truck was rear ended while parked on the street in Burbank one night. It was hit hard enough that it was launched into the Mercedes parked in front of it, which was in turn launched into the SUV parked in front of it. Both of those vehicles were totaled. Could an impact like that have damaged the differential? The truck in question is posted below. And thanks to everyone that's offered advice. I appreciate the time you took to comment.
1998 Dodge.jpg
 
Is it possible that the rear axle was changed after the accident? You need to pull the cover and see what's happening. If it was parked and hit that hard in park, it's a very good possibility it broke "something" in the sure grip.
 
I have a dana 80 of the same vintage and I’m pretty sure the cluthes need ti be replaced. It can barely get started on ice as it only spins one wheel.
 
Pop the cover and the truth will reveal it self
 
My experience with Sure-Grip is when vehicle is lifted with both back wheels in the air, if I roll the left wheel forward, the right wheel also rolls forward. It doesn't take any other force to hold them together. That may be because of light drag on the clutches but, my 2005 Ram SRT Dana 60 will spin both wheels forward on slick ice so it can't take too much pressure to lock them together. With an open differential, turn the left wheel forward and the right wheel turns backward or, when on the ground, the wheel with less traction will spin.
With my SRT Sure-Grip, there is a friction-modifier additive required when changing the gear oil.
 
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Has the diff oil and additive been ever replaced? It takes 2 bottles of friction modifier when doing a fluid change. Not just the oil with the supposed modifier in it. Change the oil and add 2 bottles of modifier to it and find a large parking lot to do some figure 8s. That just may give it a new lease on life. Kim
 
Garrett Ellison said:
Is it possible that the rear axle was changed after the accident?
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I wondered about that possibility as well, but I worked very closely with the body shop that handled the repair. I stopped by there just about every day, so it would have been difficult to replace without me knowing about it. The truck will be going into a shop for some other unrelated maintenance soon, so I'm going to take the advice of several of those commenting and have that differential checked out.
 
pt70 said:
I recently read that some newer Dodge trucks require that the emergency brake must be applied before the sure grip will work. Sounds lame to me. I'm not familiar with this. Check your owner's manual.
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That's possble. I was talking with Cass about the gear type limited slip. It doesn't use friction so runs cooler than auburn or clutch units, BUT it will not work for situations where one wheel has no traction (such as ice).
 
Cone type SGs can be rebuilt and the wedging can be adjusted. In this type of unit, the differential can be all jammed up to act like a spool. It is the rebuilder's job to NOT tighten her up that Much, so that there will still be slippage of the inside wheel during cornering. , otherwise the tires will have a shorter life. If you don't care about tire life, then tighten her up! But in winter, on ice, this can make for tricky situations.
 
As posted multiple times above, pop the cover. The answers are on the other side. And you will be able to put fresh fluid in it. Just don't use that synthetic crap.
If its open, put a powertrax lock-right in it. Problem solved.
My gm corporate 14 bolt in my diesel has a (supposed) gov-loc lsd that only locks up the wheels when one wheel spins fast enough to "throw out" the weights. It doesn't seem to work well at all.
 
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Tanker said:
I've only lived in this house since 2017 and the truck remains parked all winter. I've had to drive around another car to park up by the garage a total of three times, and each time it got stuck. Prior to that the truck was only driven on the streets of Los Angeles, so while burned up clutches as you describe may very well be causing the problem, I'd be surprised if it happened here in Pittsburgh. But this brings up another thought. The truck was rear ended while parked on the street in Burbank one night. It was hit hard enough that it was launched into the Mercedes parked in front of it, which was in turn launched into the SUV parked in front of it. Both of those vehicles were totaled. Could an impact like that have damaged the differential? The truck in question is posted below. And thanks to everyone that's offered advice. I appreciate the time you took to comment.
View attachment 1715902876
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I understand. Here's the thing. The thing. The clutch limited slip units are made to slip when going around a turn, mainly. They are not really made to just let one tire spin. That's what kills them. It'll do it pretty quickly, too. Especially if it is the Track Lock. Now the Dana Power Lock would probably not slip to begin with in that situation, as they are a much more aggressive unit.
 
33IMP said:
As posted multiple times above, pop the cover. The answers are on the other side. And you will be able to put fresh fluid in it. Just don't use that synthetic crap.
If its open, put a powertrax lock-right in it. Problem solved,
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I wholeheartedly concur with this. Those are some TOUGH units and now you have a locker. Great suggestion. BUT, he will probably have to get an open carrier to do it.
 
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