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I have a 1994 dodge ram 2500 12v auto trans 4x4. I did a vin number look up and it says it comes with 3.54 gears in it if memory serves. I am looking to put some kind of locker front and back was looking at the Detroit true track locker except they dont have anything in that high of gear ratio and I am am worried that I will lose my good highway cruising ability if I go with a lower gear ratio. I use this as a work truck mainly, I own a welding buisness and mostly do on road, but sometimes I need to go offroad to get to a piece of equipment I need to repair and I want it to be more capable offroad.

Do any of you have any experiance with the truetrac lockers?

Do you have any other suggestions?

Also been trying to find out if my truck has a dana 80 or 70 in it I have found places on the internet saying it could have either of those and the vin number lookup does not say.
 

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Your truck should have the dana 70 stock duallys and manuals got the 80. You also can’t 100 percent trust those vin lookups for ratio and since you don’t have hubs in the front I would not recommend any type of locker in the front.... if you do anything get a locking hub conversion and Detroit tru track they work great in front axles. Are you sure the rear end is open? It is pretty common for diesel 4x4s to have limited slip from the factory.
 

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Limited Slip carriers are what the 2nd gen trucks came with if equipped. You can tell if you have one by jacking the rear axle off the ground and spinning one tire at a time with the transmission in neutral and the e-brake off. When spinning one side by hand, if the other side turns in the same direction then you have a LS carrier. If it spins in the opposite direction then you have an open carrier. Sometimes there's a build sheet sticker in the glovebox.

The Truetrac is what the newer gen trucks came with and they're good. Lockers are aggressive and should only be used if you need that kind of aggressive engagement like extreme off roading or roack crawling.

Dont ever use a traction carrier in the front unless its an air locker or e-locker because they cause the front axle to become dangerous to drive on rainy, slippery roads. Its said that anything but open up front will result in being in the ditch in the winter.

That said, air/electric lockers are the best by far. They give the best of both worlds.
 

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The factory limited slip rear (in a Dana 80 at least) had the steel and friction plates stacked such that not all of them were actually doing anything. If you have a factory limited slip (which a lot of the 4x4 trucks did) then you can get a lot better offroad traction for the price of some diff oil and gasket. Do a google search for limited slip plate restacking, its not a new thing and has been covered a bunch (not unique to dodge or cummins). I did it and it works pretty well.
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The Truetrac is what the newer gen trucks came with and they're good. Lockers are aggressive and should only be used if you need that kind of aggressive engagement like extreme off roading or roack crawling.

Dont ever use a traction carrier in the front unless its an air locker or e-locker because they cause the front axle to become dangerous to drive on rainy, slippery roads. Its said that anything but open up front will result in being in the ditch in the winter.
Tru track is also available aftermarket for about any differential imaginable and they work ok in the front. But yes you are right any non selective locker is downright dangerous on slippery road and not recommend at all if you don’t have locking hubs. My old Jeep had factory LS front and rear it was scary in the winter.
 

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I ran a Detroit locker in the front of my 98.5 for 178k miles in both snow and rain and never wound up in the ditch. They will be a little slow to react on a snowy highway at speed while engaged, but that’s about it. A manual locker in the front is not for everyone, however it will not magically throw you in the ditch.

My 98.5 manual had a “hybrid” Dana 80, 80 center section with 70 tubes and brakes. The limited slip became “ loose” within about 60k, but I was wheeling a bunch.
 

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I ran a Detroit locker in the front of my 98.5 for 178k miles in both snow and rain and never wound up in the ditch. They will be a little slow to react on a snowy highway at speed while engaged, but that’s about it. A manual locker in the front is not for everyone, however it will not magically throw you in the ditch.

My 98.5 manual had a “hybrid” Dana 80, 80 center section with 70 tubes and brakes. The limited slip became “ loose” within about 60k, but I was wheeling a bunch.
I think the point worth making for anyone unaware is simply that anything but an open carrier up front without lockout hubs will cause a potential unsafe vehicle on the open road.

And also noting the internet rumor is false about the "hybrid" Dana 80 because it is identical to the dual wheel Dana 80, except for spindles which accommodate the bud wheels. Same tube size, same brakes... :thumbup:
 

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I think the point worth making for anyone unaware is simply that anything but an open carrier up front without lockout hubs will cause a potential unsafe vehicle on the open road.

And also noting the internet rumor is false about the "hybrid" Dana 80 because it is identical to the dual wheel Dana 80, except for spindles which accommodate the bud wheels. Same tube size, same brakes... :thumbup:
What do you base your claim on, do you have one of these trucks with a locker in the front without lockout hubs?

So by your own explanation it contains both parts of a Dana 80 and 70 parts, hybrid would be a fitting word.

https://www.cumminsforum.com/forum/98-5-02-powertrain/558243-wonder-what-hybrid-dana-80-read-thread.html
 

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tjpatte, were you still using the CAD when you had the locker in?

Don't make the issue about how technically appropriate it is to call it a hybrid. The issue is about the spread of misinformation about the tubes and brakes being different.
 

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Just curious, why is it unsafe to have a locker in the front without lockout hubs??

In my younger days I had a little Toyota truck (don't judge , it was all I could afford at the time) . I put an eaton truetrac in the font of it (and a regular Detroit locker in the back). While that little truck had manual lockout hubs, I used to just leave them locked in all winter and just shift the transfer case in and out of 4x4 as needed until spring. It was a long time ago, but I don't recall any additional negative handling as a result (of course a small truck with both a suspension and a body lift and way over-sized tires doesn't handle real good to start with I suppose) .
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Just curious, why is it unsafe to have a locker in the front without lockout hubs??
For one, you read that it's unsafe on the internet, so therefore it must be true.

I have never had any problems with TrueTrac or Detroit Locker diffs in the front, locking hubs or not, but sure wouldn't install either in an axle with a CAD.
And I'd take either kind over a clutch type LSD for winter use.

Does that mean they're foolproof in a front application? Of course not. Keep in mind that we now have lane assist, lane changing assist, park assist, adaptive cruise control, and similar nannies for a reason.
 

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A standard stacked-clutch limited slip is extremely dangerous on icy roads (plain old wet roads too in some cases) if the hubs or CAD are not disengaged. This is because a certain amount of traction is required to overcome the clutch packs and let the wheels turn at different speeds. If the road surface can't provide that traction, you effectively have a spool in the front axle and the resultant loss of control in turns. If you can unlock the hubs or the CAD, the wheels will do whatever they want and it doesn't matter what the differential is doing.

A co-worker of mine who had a CAD delete and a limited slip in his front axle in his old race truck took me for a ride on the street when I was considering putting a limited slip in my front axle, and it was apparent from the passenger seat that there was enough resistance in the differential that it would have been horrendously unsafe when trying to turn on ice in 4wd.

Of the mechanical lockers, there are enough different methods of operation that they can't all be lumped in the same category. Some might be, some aren't.
 

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tjpatte, were you still using the CAD when you had the locker in?

Don't make the issue about how technically appropriate it is to call it a hybrid. The issue is about the spread of misinformation about the tubes and brakes being different.

Yep, with the factory vacuum actuator.

I was just saying the rear axle is neither an 80 or 70.
 

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What do you base your claim on, do you have one of these trucks with a locker in the front without lockout hubs?

So by your own explanation it contains both parts of a Dana 80 and 70 parts, hybrid would be a fitting word.

https://www.cumminsforum.com/forum/98-5-02-powertrain/558243-wonder-what-hybrid-dana-80-read-thread.html
Obviously you're insulted by my response... My claim is based on years of common knowledge information and owning many 4wd trucks throughout my life... Point is, its not safe, thats all.
That said, I absolutely dont care who chooses to install a LS or locker in their front differential of their own truck, but just that its important for someone to know if they do then they're potentially creating a dangerous vehicle. It would suck to find out something like that after the fact, no?
And if sharing that kind of information is frowned upon then I guess I'm in the wrong place...

As for the "hybrid" discussion... Again, I'm only sharing information for those who may or may not know. Dont read too much else into it. If you want to call the 80 a hybrid just because it shares the same outer bearing as the 70 then thats up to you, but you might want to also call the 70 a hybrid then as well since it shares a part with the 80. Or...is that confusing things more than the rumor already in place. :confused013:

Just curious, why is it unsafe to have a locker in the front without lockout hubs??

In my younger days I had a little Toyota truck (don't judge , it was all I could afford at the time) . I put an eaton truetrac in the font of it (and a regular Detroit locker in the back). While that little truck had manual lockout hubs, I used to just leave them locked in all winter and just shift the transfer case in and out of 4x4 as needed until spring. It was a long time ago, but I don't recall any additional negative handling as a result (of course a small truck with both a suspension and a body lift and way over-sized tires doesn't handle real good to start with I suppose)
Just like the rear tires, and why its illegal to run a spool, the left and right tires must be able to freely differentiate speeds while turning and going around corners. This is especially important in the front axle otherwise the tires can easily loose traction on slippery surfaces and then you're out of control. This is why you wont find a LS carrier or a manual locker in the front of any OEM vehicle. If there's any traction adding carrier in the front of an OEM vehicle then its an air or electric locker.

And as already noted, if you have lock out hubs then you can run whatever you want in the front carrier since the tires are separated from the carrier during lock out. But a CAD front axle is NOT THE SAME as lock out hubs and will also create erratic carrier feedback to the tires while in 2wd. :thumbup:
 

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Obviously you're insulted by my response... My claim is based on years of common knowledge information and owning many 4wd trucks throughout my life... Point is, its not safe, thats all.
That said, I absolutely dont care who chooses to install a LS or locker in their front differential of their own truck, but just that its important for someone to know if they do then they're potentially creating a dangerous vehicle. It would suck to find out something like that after the fact, no?
And if sharing that kind of information is frowned upon then I guess I'm in the wrong place...

As for the "hybrid" discussion... Again, I'm only sharing information for those who may or may not know. Dont read too much else into it. If you want to call the 80 a hybrid just because it shares the same outer bearing as the 70 then thats up to you, but you might want to also call the 70 a hybrid then as well since it shares a part with the 80. Or...is that confusing things more than the rumor already in place. :confused013:



Just like the rear tires, and why its illegal to run a spool, the left and right tires must be able to freely differentiate speeds while turning and going around corners. This is especially important in the front axle otherwise the tires can easily loose traction on slippery surfaces and then you're out of control. This is why you wont find a LS carrier or a manual locker in the front of any OEM vehicle. If there's any traction adding carrier in the front of an OEM vehicle then its an air or electric locker.

And as already noted, if you have lock out hubs then you can run whatever you want in the front carrier since the tires are separated from the carrier during lock out. But a CAD front axle is NOT THE SAME as lock out hubs and will also create erratic carrier feedback to the tires while in 2wd. :thumbup:

Nope, not insulted. I just hear misinformation like this quite a bit from people, who have no experience with the issue, and then post like they know something about it. I just wanted the OP to know that there are people out there that actually have the product and experience with it.

Spools are locked all the time, Detroit lockers only lock when power is being put to pinion gear so basically you can "coast" through a turn and it will act like an open diff.
 

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Just like the rear tires, and why its illegal to run a spool, the left and right tires must be able to freely differentiate speeds while turning and going around corners.

This is especially important in the front axle otherwise the tires can easily loose traction on slippery surfaces and then you're out of control. This is why you wont find a LS carrier or a manual locker in the front of any OEM vehicle. If there's any traction adding carrier in the front of an OEM vehicle then its an air or electric locker.
Never knew that it's illegal to run a spool, but it kinda makes sense.

Anyway, there used to be OE clutch type LSDs available for the front. Of course, now I can't remember any other examples, but I do have a GM 1-ton with one.
 

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Can you elaborate on this? I'm wanting to disagree but perhaps you know something I don't.
The CAD unit only disconnects the passenger side tire from the carrier. Therefore the drivers side tire still spins the carrier in the forward direction, and the non-spinning driveshaft causes the spider gears to spin which then turns the passenger side half shaft in the reverse direction.

With an open carrier there is no feedback, but if you use a LS or locker carrier then you'll cause the left tire to drag more than the right tire as its forced to spin the carrier unit, and also spin the driveshaft, while the right tire spins freely.
 

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Nope, not insulted. I just hear misinformation like this quite a bit from people, who have no experience with the issue, and then post like they know something about it. I just wanted the OP to know that there are people out there that actually have the product and experience with it.

Spools are locked all the time, Detroit lockers only lock when power is being put to pinion gear so basically you can "coast" through a turn and it will act like an open diff.
Glad you're not insulted. :thumbup:
Because I'm also going to point out that a Detroit Locker is fully engaged all the time. While turning, the change in speed of the left and right tire will cause the locker teeth to disengage and pop. This is where Detroit Lockers get their name for being loud and aggressive on the street. They do not coast through a turn. The Truetrac will though...

Never knew that it's illegal to run a spool, but it kinda makes sense.

Anyway, there used to be OE clutch type LSDs available for the front. Of course, now I can't remember any other examples, but I do have a GM 1-ton with one.
Your GM 1 ton has lock out hubs...
And I should have noted that only modern 4wd trucks have e-lockers up front. Anything older came with lock out hubs.
 

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The CAD unit only disconnects the passenger side tire from the carrier. Therefore the drivers side tire still spins the carrier in the forward direction, and the non-spinning driveshaft causes the spider gears to spin which then turns the passenger side half shaft in the reverse direction.
Slight disagreement here, KATOOM. I'd think that the spider gears spin, driven by the left side, but the right side stays stationary.

And yes, that 1-ton does have hubs.
 
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