Which limited slip is best?

[fastpakr]

Isn’t that what a c-clip eliminator is for? Nevermind that, how cheap do you want to let it go?

You can't do that on an SLA setup can you? Mine would work for a standard rotation 35 other than the retention issue. Not sure how you'd use it on a reverse rotation 35.

 

[Lefty]

Others have recommended the Trak Loc too. I don't tow a trailer or spend much time off road. I just want something to make for a more stable ride or maybe just keep me from getting stuck on snow days. I may live in the city but our street is always one of the last to be plowed. Sometimes it takes a week or longer especially after a six inch snowfall. It doesn't happen often, maybe once or twice avery winter. We've had as much as ten inches at one time.

After reading you and others, I am willing to bet that a Trak LoC clutch may wear out but only after 100,000 miles of moderate driving.. That's decent. I'm also willing to bet than any of those recommended here will be a very nice upgrade to an open wheel diff.

Maybe it's worth the mention, but I'm going to buy a new spare tire too, one with the same diameter as my larger 4 tire set. It's an important consideration should a rear tire ever go flat.

I've crawled under enough Rangers and Explorers at the Upull yard looking for that ideal axle swap or even just a differential. Everything I've seen has been what it is: rusty, leaking, many miles on those odometers, just plain junk.

I've booked a date to have the job done, told the shop that I'm open to suggestions. There is a shortage of parts these days. What is available, may be a factor too.

Thanks once again for the real world schooling. Now I know what's out there and what to expect.

 

[lil_Blue_Ford]

Others have recommended the Trak Loc too. I don't tow a trailer or spend much time off road. I just want something to make for a more stable ride or maybe just keep me from getting stuck on snow days. I may live in the city but our street is always one of the last to be plowed. Sometimes it takes a week or longer even after a six inch snow fall. It doesn't happen often, maybe once or twice avery winter.

After reading you and others, I am willing to bet that a Trak LoC clutch may wear out but only after 100,000 miles of moderate driving.. That's decent. I'm also willing to bet than any of these will be a very nice upgrade to my open wheel diff.

The trac loc differential is in my opinion plenty adequate for street use. With or without extra clutches. The clutches may wear faster if you pack the thing, but when I tore apart the Explorer rear for my green Ranger project with like 167k, the clutches still looked in pretty good shape. I put new Yukon clutches in and used one of the old clutch disks on each side (replacing a steel). Seems to have worked out just fine. It’s AWD, so all I can do is squeak the rear tires on a turn, but that’s fine. I wanted to be certain of being able to put all of the power to the ground without having to spring for a locker.

 

[lil_Blue_Ford]

You can't do that on an SLA setup can you? Mine would work for a standard rotation 35 other than the retention issue. Not sure how you'd use it on a reverse rotation 35.

I’m not sure how much of an issue it would be on an SLA setup, the axle is pretty much stuck in place on those, you pretty much have to pop the upper BJ loose to pull a shaft on those. Not sure if suspension movement would be enough to move the axle without a retainer or not. I know the little C-clip doesn’t seem to do a ton on those. Not sure there’s any way to do an eliminator either. The old TTB with a spring would probably be ok, i don’t know if it matters for the differential if it’s a standard or reverse rotation. Something I never really looked into.

 

[gw33gp]

If you do the math on the Torsen, you will find that the torque bias that it takes to make it differential under load is so high that it is effectively locked. That is the mechanism that "locks" it.

The amount of gas pedal that it takes to chirp the inside tire on a turn is significantly less than the amount of gas pedal that it takes to chirp the inside tire with a clutch type diff. That was my point, and why I suggested to the op that the clutch type is likely a better choice for his needs.

I am sure if someone actually did do the math on the Torsen differential, neither you or I would understand it.

The Ranger Torsen differential is a T-2 (planetary type gears) which has a torque bias rating of 2.1-1. This is a higher bias than a clutch type but is nowhere near effectively locked. The T-1 Torsen (spur gear-worm gear combination) has a higher bias and comes closer to being locked but still can't be considered locked. There is also a Torsen T-2R (planetary gears plus clutch plates) which is preloaded and also has a higher torque bias than the T-2, but still does not lock.

If you can show me math or any other reliable information that indicates a T-2 Torsen can lock up, I will study it. I don't think you can find anything reliable that says the T-2 Torsen is anything other than a high bias differential.

Here is a link on the T-1.

It is not the planetary type of the T-2 but gives you an idea of how the Torsen works. It does come near lock up due to the worm gears but the T-2 does not have worm gears give it that near lock up feature.

 

[rubydist]

Actually I do understand the math (I am a mechanical engineer), which is why I posted what I posted: "the torque bias that it takes to make it differential under load is so high that it is effectively locked" If the torque bias required for the mechanism to differential is higher than what is able to be provided by the tire friction, then it is effectively locked.

We don't need to clutter this thread with this - I just posted my personal experience and why that is the case. You don't have to agree with me.

 

[sgtsandman]

You can't do that on an SLA setup can you? Mine would work for a standard rotation 35 other than the retention issue. Not sure how you'd use it on a reverse rotation 35.

The C-Clip eliminators that I've seen are only for solid axles that otherwise have nothing to hold the axles shafts in place. They mount on the end of the axle tube. So I can't see how one could make something like that work with the external CV shafts. Of course, there is the knuckle and bearings in the front that are holing the CV Shafts in place too. I can't see the C-Clips doing much of anything in an SLA.

 

[85_Ranger4x4]

I have only had the clutch type, not crazy about it in the winter. I need 4wd to keep the rear from passing the front.

My dd's have always been open diff 4wd's, they are more predictable and directionally stable. My current one has a selectable locker but I have yet to need it in snow.

 

[00t444e]

Actually I do understand the math (I am a mechanical engineer), which is why I posted what I posted: "the torque bias that it takes to make it differential under load is so high that it is effectively locked" If the torque bias required for the mechanism to differential is higher than what is able to be provided by the tire friction, then it is effectively locked.

That's not what a locked differential is.

 

[RonD]

Locking differential from Dodge: https://parkingzonepost.files.wordpress.com/2011/02/pblock.jpg

 

[fastpakr]

That's not what a locked differential is.

No kidding?

 

[lil_Blue_Ford]

I have only had the clutch type, not crazy about it in the winter. I need 4wd to keep the rear from passing the front.

My dd's have always been open diff 4wd's, they are more predictable and directionally stable. My current one has a selectable locker but I have yet to need it in snow.

So, I’ve found that the clutch type if it’s been modified, tends to have a pretty predictable lockup but 4x4 definitely gets used more often. It almost acts like a locker in the winter. A normal clutch type can have a little more unpredictability in the winter.

A locker is very predictable but also requires 4x4 to be used a lot more because of a tendency to push the front end straight. Found that out the first winter I drove the F-150 with a Lock-Right in the rear. I had traction for days in 2wd… as long as I only wanted to go straight. Needed the front end digging to pull me around turns. I got to where I lock in the front hubs unless I’m doing highway driving in decent winter weather and use 4x4 as needed in the winter to keep me on the road. Try turning on your rear locker in snow in 2wd and you’ll see what I mean.

Lockers, and things that work somewhat close to them, at least around here, you can usually feel it try to kick the back end out, so I’ll back off the skinny pedal right away and try rolling back on it gently. In a stock limited slip, the back still likes to try to pass you, but if you have extra clutches and little to no friction modifier, it will usually respond more positively to throttle work to keep it steady. Or at least in my experience around here that’s the case.

 

[00t444e]

So, I’ve found that the clutch type if it’s been modified, tends to have a pretty predictable lockup but 4x4 definitely gets used more often. It almost acts like a locker in the winter. A normal clutch type can have a little more unpredictability in the winter.

A locker is very predictable but also requires 4x4 to be used a lot more because of a tendency to push the front end straight. Found that out the first winter I drove the F-150 with a Lock-Right in the rear. I had traction for days in 2wd… as long as I only wanted to go straight. Needed the front end digging to pull me around turns. I got to where I lock in the front hubs unless I’m doing highway driving in decent winter weather and use 4x4 as needed in the winter to keep me on the road. Try turning on your rear locker in snow in 2wd and you’ll see what I mean.

Lockers, and things that work somewhat close to them, at least around here, you can usually feel it try to kick the back end out, so I’ll back off the skinny pedal right away and try rolling back on it gently. In a stock limited slip, the back still likes to try to pass you, but if you have extra clutches and little to no friction modifier, it will usually respond more positively to throttle work to keep it steady. Or at least in my experience around here that’s the case.

I have had a rear auto locker in 4 vehicles, drive in the snow every winter and never had any issues with it not turning in 2wd.

 

[don4331]

Maybe it's worth the mention, but I'm going to buy a new spare tire too, one with the same diameter as my larger 4 tire set. It's an important consideration should a rear tire ever go flat.

The new spare same size is a good idea - you just need to include in your tire rotation - otherwise a new spare is significantly larger than a worn out tire. I always put the spare on the front, and the front on the rear when I have a flat for that reason - 50 miles on a 235/75R15 when rest of the tires are 31x10.5R15 would be really hard on "clutch" differential.

 

[gw33gp]

Actually I do understand the math (I am a mechanical engineer), which is why I posted what I posted: "the torque bias that it takes to make it differential under load is so high that it is effectively locked" If the torque bias required for the mechanism to differential is higher than what is able to be provided by the tire friction, then it is effectively locked.

We don't need to clutter this thread with this - I just posted my personal experience and why that is the case. You don't have to agree with me.

A true locked differential is one with welded spider gears or spooled. I have a race car with that, and it is basically no differential. It is like hitting the brakes when turning at slow speeds because both tires are trying to slide in opposite directions.

If you understand the math, please share it with me. You can do a private message if you don't want to clutter up this thread. What you have said so far is not math. Is a bunch of words that are not backed by math. I am also an engineer with enough physics and calculus that I can probably understand it and possibly figure out your error.

A locked differential does not have a torque bias. It sends 50% of the torque available to each axle all the time. An LSD sends a percentage of the torque of the axle with the least traction to the axle with the most traction. The T-1 Torsen can approach sending 100% of the torque of the axle with the least traction to the axle with the most traction but the T-2 Torsen (what comes in the Ranger) cannot get near that. The T-2 Torsen just has a higher torque bias than a stock clutch type LSD. You put one of your rear wheels in the air and put the transmission in gear at idle and let out slowly on the clutch, that tire in the air will just spin with a T-2 Torsen. A locked deferential would drive both wheels equally and your vehicle would move forward. If you accelerate (increase engine rpm) while doing this with a T-2 Torsen, you should move forward slowly because you are increasing the torque to the axle with the least traction and the stalled axle will get a percentage of that.

I also agree that a stock clutch type LSD is better suited for street driving.