I tested out my front and rear Detroit Truetrac LSDs

While TTs don't have the off road performance of a locker; they work quite well in most situations.
I watched an XJ owner in Moab several years ago drive into and out of Mickey's Hot Tub with front and rear TTs.
Never had an issue with mine even in the rocks. Went to the locker just BC it is less effort and more precise than dealing with the brake technique and TT

P.S. your results may vary...
 
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While TTs don't have the off road performance of a locker; they work quite well in most situations.
I watched an XJ owner in Moab several years ago drive into and out of Mickey's Hot Tub with front and rear TTs.
No doubt, all four tires remain in contact with the surface of that bowl most of the way and at no point would you be on one tire each axle that would prevent that from happening. A 100% stock brand-new 2021 Ford Bronco with no lockers is on video doing that same bowl. Lockers are definitely not required for Mickey's Hot Tub. Skip to near the very end when he walks it out.

 
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No doubt, all four tires remain in contact with the surface of that bowl most of the way and at no point would you be on one tire each axle that would prevent that from happening. A 100% stock brand-new 2021 Ford Bronco with no lockers is on video doing that same bowl. Lockers are definitely not required for Mickey's Hot Tub. Skip to near the very end when he walks it out.

Yeah but TT dont clang and bang like my Autos do when I throw it in reverse at the Mall.
 
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Trutrac front and rear , Dana 44 Dana 30

3938BEC7-1FBA-4226-A073-63F6B1B4B2AB.png
 
The picture is deceiving, driver front tire is firmly planted and climbing up Dicky Bell .
Very little throttle , I was trying to steer off of the side to keep from flipping
 
A new Jeep owner needs to decide what they will use their vehicle for; how much time it's used as a daily driver or trail vehicle, the type of trails they will be exploring and what their budget will support. Whether it's moderate trails (dirt trails with occasional rocks. more difficult trails (some rocks with occasional dirt) or hard core trails (primarily rock) which will determine the type of traction device they install.
Too many new and inexperienced Jeep owners build their Jeeps more than their driving skills can handle and get themselves into dangerous situations.
Personally I believe Jeep owners should drive their Jeep stock for at least a year so they can develop driving skills and gain trail experience before building their Jeep.
Most Jeep owners can do moderate trails with a limited slip which will provide time for them to gain experience and decide if a locker is really what they need...
I ran the Detroit TT for many years until I reached a point where the type of trails that I was exploring were too dangerous with a limited slip and I decided to move on to a Detroit locker in the rear and ARB up front. This setup worked great in the rocks, dirt trails and as a daily driver, but when it came to ice, snow and mud... the rear locker with a manual transmission could create situations where you needed to really pay attention and know your vehicle.
I am sure some forum members will disagree with me, but I have seen too many Jeep owners hurt due to lack of trail driving skills and vehicle experience.
 
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A new Jeep owner needs to decide what they will use their vehicle for; how much time it's used as a daily driver or trail vehicle, the type of trails they will be exploring and what their budget will support. Whether it's moderate trails (dirt trails with occasional rocks. more difficult trails (some rocks with occasional dirt) or hard core trails (primarily rock) which will determine the type of traction device they install.
Too many new and inexperienced Jeep owners build their Jeeps more that their driving skills can handle and get themselves into dangerous situations.
Personally I believe Jeep owners should drive their Jeep stock for at least a year so they can develop driving skill and gain trail experience before building their Jeep.
Most Jeep owners can do moderate trails with a limited slip which will provide time for them to gain experience and decide if a locker is really what they need...
I ran the Detroit TT for many years until I reached a point where the type of trails that I was exploring were too dangerous with a limited slip and I decided to move on to a Detroit locker in the rear and ARB up front. This setup worked great in the rocks, dirt trails and as a daily driver, but when it came to ice, snow and mud... the rear locker with a manual transmission could create situations where you needed to really pay attention and know your vehicle.
I am sure some forum members will disagree with me, but I have seen too many Jeep owners hurt due to lack of trail driving skills and vehicle experience.
Well said. My deciding factor of going with the TT was I want to know and learn as I build it. Driving skill, understanding what you need and why. It seems like a lot of veteran tj guys have had many different setups and I think everyone just wants the best and skip to it. But you are foregoing valuable experience learning what it can do and why while learning to drive it on your area trails.
 
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I have TT's front and rear and love them, particularly as a stick shifter who drives on snow. But honestly I would not recommend them to a new wheeler. Not because they require special skill or anything, but because you're missing out on a lot of learning to be had with open diffs. Those who run open/open for a while are usually surprised how capable their vehicle is. The problem with LSDs and autolockers is that you don't know when you could have made it without them, so you aren't necessarily learning as much from each obstacle as you could be. You may credit your success to the traction device when you could have made it through with open diffs - you just don't know. And you may find yourself putting tires in the air a lot, in which case you would be better served with lockers instead of LSDs.
 
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If I'm reading this all correctly, a locker can transmit 100% torque to one wheel.
A truetrac transmits only a ratio of torque from the wheel with less traction to the wheel with more traction. Never 100%.
Would a front truetrac be less prone to busting the front axle shafts/axle u joints than a true locker?
(provided someone isn't being stupid like using full throttle with the steering cranked)

I already have a selectable rear locker and am pondering the options for a front traction aid.
 
If I'm reading this all correctly, a locker can transmit 100% torque to one wheel.
A truetrac transmits only a ratio of torque from the wheel with less traction to the wheel with more traction. Never 100%.
Would a front truetrac be less prone to busting the front axle shafts/axle u joints than a true locker?
(provided someone isn't being stupid like using full throttle with the steering cranked)

I already have a selectable rear locker and am pondering the options for a front traction aid.

As much as I had front wheels in the air, from traction stand point, truetrack would be the last thing I put in front.
Truetrack in the back and selectable in the front, that is different story.
 
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If I'm reading this all correctly, a locker can transmit 100% torque to one wheel.
A truetrac transmits only a ratio of torque from the wheel with less traction to the wheel with more traction. Never 100%.

Would a front truetrac be less prone to busting the front axle shafts/axle u joints than a true locker?
(provided someone isn't being stupid like using full throttle with the steering cranked)

I already have a selectable rear locker and am pondering the options for a front traction aid.
Correct on the first paragraph. However, a front Truetrac is useless on all but flat terrain in my personal experience, I had f/r Truetracs on my first TJ for about a year before yanking both out and replacing them with lockers.

Your front axle only needs to have its axle shafts upgraded to chromolly, like 4340, inner and outer 27 spline shafts. No need to go with 30 spline shafts up front with 35" tires and a locker. I broke a factory front axle shaft on an extremely tough trail with 35" tires and f/r lockers but once I upgraded the shafts to 4340 inner/outer shafts, no more problems. Keep in mind too that the front axle seldom sees more than about 50% of the load that the rear axle commonly sees.
 
As much as I had front wheels in the air, from traction stand point, truetrack would be the last thing I put in front.
Truetrack in the back and selectable in the front, that is different story.
For the moderate wheeler who street drives their TJ as well, I agree this is a great combo. Gets you through a TON of wheeling (minus hardcore rock crawling). I have an auto locker up front and trutrac rear but if you can pony up the dough for a selectable locker upfront, that’s the way to go.
 
I have chromoly shafts front and rear.

I'm sure a front selectable locker is superior for ultimate traction, but I'd imagine a front TT is still better than an open diff for muddy trails while being completely transparent on the road.
 
I have chromoly shafts front and rear.

I'm sure a front selectable locker is superior for ultimate traction, but I'd imagine a front TT is still better than an open diff for muddy trails while being completely transparent on the road.
A front locker like an Aussie or No-Slip is also completely transparent on the road when you're in 2wd. I had a No-Slip in my front axle in my previous TJ and I absolutely could not tell it was there until I shifted into 4x4. It was virtually silent and did not affect steering whatsoever.

Other lunchbox lockers are equally well-behaved as the N0-Slip but those click-ratchet quietly while making slow-speed turns like in parking lots.
 
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I'm sure a front selectable locker is superior for ultimate traction, but I'd imagine a front TT is still better than an open diff for muddy trails while being completely transparent on the road.

When one of the wheels starts spinning in the air, TT will be no better than open dif.


As long as you understand what you are facing and understand limitations of what you have. Simply don't want you to make uninformed decision.
 
Gear-driven limited slips transmit a ratio of torque bias, whereas clutch-driven limited slips transmit a preset amount of torque bias.

Gear driven limited slips usually have a ratio of around 3.5:1 (most Truetrac models) or 4:1 to 5:1 (most Torsen models). Some special builds wil have different ratios, like the 2.5:1 ratio Torsen differential optioned in the front F150 Tremor/Raptor axle.

Clutch-driven limited slips have a bias amount anywhere between 40-200 ft-lbs. This is preset from the factory and is not adjustable on the fly. This can be adjusted permanently by installing different preload springs and clutch packs.


Let’s say you have one wheel on pavement and another stuck in the mud. Let’s say the mud provides 100 ft-lbs of resistance to the sunken tire.

If you have an open differential, you can apply up to 100 ft-lbs to both tires, but no more, for a total of 200 ft-lbs of propelling torque.

If you have a Truetrac, you can apply up to 3.5X the lower amount to the higher traction wheel, or 350 ft-lbs, for a total of 450 ft-lbs of propelling torque.

If you have a clutch-driven limited slip preloaded to 50 ft-lbs, you can apply up to 100+50 ft-lbs to the wheel on pavement, for a total of 250 lbs of propelling force.

If you have a locker, you can apply infinite torque (well, up until you snap a shaft at around 2,000 ft-lbs to be more accurate) to each wheel.


Now, let’s say you get to a new spot where one wheel is in the air, and the other on pavement. The wheel in the air is free to spin.

The open differential can apply 0 ft-lbs to either wheel, as the wheel in the air just spins.

The gear driven limited slip does the exact same. Since one wheel spins freely, the carrier sees no torque with which to multiply to the pavement wheel.

(But, you remember an old trick your grandpa taught you: pull the parking brake and power through it! How does this work? Say you apply the parking brake with force to resist 200 ft-lbs at each wheel. The wheel in air and the wheel on the pavement both are provided with a 200 ft-lbs resistance. But since the wheel in the air now has resisting torque, the differential can now multiply that torque and send it to the wheel on the pavement. So now that wheel is powered with 700 ft-lbs, minus the 200 of the parking brake. So now the whole car has a net propulsive torque of 500 ft-lbs!)

The clutch driven limited torque in this scenario is only able to apply 50 ft-lbs of torque to the wheel on the pavement. Braking tricks rarely assist here.

The locker can still apply infinite torque to either wheel, and thus it can apply as much torque as is needed to the wheel on the pavement, limited only by the strength of the axle shaft (or of course traction). So in this case the car gets up to 2,000 ft-lbs of propelling torque.
 
Gear-driven limited slips transmit a ratio of torque bias, whereas clutch-driven limited slips transmit a preset amount of torque bias.

Gear driven limited slips usually have a ratio of around 3.5:1 (most Truetrac models) or 4:1 to 5:1 (most Torsen models). Some special builds wil have different ratios, like the 2.5:1 ratio Torsen differential optioned in the front F150 Tremor/Raptor axle.

Clutch-driven limited slips have a bias amount anywhere between 40-200 ft-lbs. This is preset from the factory and is not adjustable on the fly. This can be adjusted permanently by installing different preload springs and clutch packs.


Let’s say you have one wheel on pavement and another stuck in the mud. Let’s say the mud provides 100 ft-lbs of resistance to the sunken tire.

If you have an open differential, you can apply up to 100 ft-lbs to both tires, but no more, for a total of 200 ft-lbs of propelling torque.

If you have a Truetrac, you can apply up to 3.5X the lower amount to the higher traction wheel, or 350 ft-lbs, for a total of 450 ft-lbs of propelling torque.

If you have a clutch-driven limited slip preloaded to 50 ft-lbs, you can apply up to 100+50 ft-lbs to the wheel on pavement, for a total of 250 lbs of propelling force.

If you have a locker, you can apply infinite torque (well, up until you snap a shaft at around 2,000 ft-lbs to be more accurate) to each wheel.


Now, let’s say you get to a new spot where one wheel is in the air, and the other on pavement. The wheel in the air is free to spin.

The open differential can apply 0 ft-lbs to either wheel, as the wheel in the air just spins.

The gear driven limited slip does the exact same. Since one wheel spins freely, the carrier sees no torque with which to multiply to the pavement wheel.

(But, you remember an old trick your grandpa taught you: pull the parking brake and power through it! How does this work? Say you apply the parking brake with force to resist 200 ft-lbs at each wheel. The wheel in air and the wheel on the pavement both are provided with a 200 ft-lbs resistance. But since the wheel in the air now has resisting torque, the differential can now multiply that torque and send it to the wheel on the pavement. So now that wheel is powered with 700 ft-lbs, minus the 200 of the parking brake. So now the whole car has a net propulsive torque of 500 ft-lbs!)

The clutch driven limited torque in this scenario is only able to apply 50 ft-lbs of torque to the wheel on the pavement. Braking tricks rarely assist here.

The locker can still apply infinite torque to either wheel, and thus it can apply as much torque as is needed to the wheel on the pavement, limited only by the strength of the axle shaft (or of course traction). So in this case the car gets up to 2,000 ft-lbs of propelling torque.
Wow. I’ve never completely understood LSDs but that’s probably the best explanation I’ve seen. Thank you
 
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But, you remember an old trick your grandpa taught you: pull the parking brake and power through it! How does this work? Say you apply the parking brake with force to resist 200 ft-lbs at each wheel. The wheel in air and the wheel on the pavement both are provided with a 200 ft-lbs resistance. But since the wheel in the air now has resisting torque, the differential can now multiply that torque and send it to the wheel on the pavement. So now that wheel is powered with 700 ft-lbs, minus the 200 of the parking brake. So now the whole car has a net propulsive torque of 500 ft-lbs!

The clutch driven limited torque in this scenario is only able to apply 50 ft-lbs of torque to the wheel on the pavement. Braking tricks rarely assist here.

The locker can still apply infinite torque to either wheel, and thus it can apply as much torque as is needed to the wheel on the pavement, limited only by the strength of the axle shaft (or of course traction).
The grandpa technique helps but not much, if at all, if you're in difficult conditions. I used braking technique EXTENSIVELY when I had f/r Detroit Truetracs and it only helped some in easier situations. It became pretty much completely ineffective when I got onto tougher trail conditions that lifted a tire up off the ground. I ended up replacing both of them with lockers and never looked back.