Limited Slip vs. Locker

apimpdad · #1 (**permalink**) 10-02-2007, 08:49 PM

so i was considering getting a detroit locker in the rear of my truck, but i have seen countless reviews on how they are not very good on the road, but off road is amazing. A few of my friends have just a factory limited slip on their trucks (02 f-150, 74 bronco, 97 f-150, 06 dodge 2500) and they walk through everything i cant, and the 02 ford and 74 bronco are completely stock!!!!! i figured i should just get a limited slip in the rear because it is better on road and decent off road and a locker in the front of my tundra. what do you guys think?

jjc · #2 (**permalink**) 10-03-2007, 06:50 AM

Quote:

Originally Posted by apimpdad

so i was considering getting a detroit locker in the rear of my truck, but i have seen countless reviews on how they are not very good on the road, but off road is amazing. A few of my friends have just a factory limited slip on their trucks (02 f-150, 74 bronco, 97 f-150, 06 dodge 2500) and they walk through everything i cant, and the 02 ford and 74 bronco are completely stock!!!!! i figured i should just get a limited slip in the rear because it is better on road and decent off road and a locker in the front of my tundra. what do you guys think?

I ran a Detroit in the back of my '74 Bronco and it was the best locker I've ever owned. They are fine on the road once you get used to driving with one, no different from a No-Slip really. I even drove my Bronco on ice and snow with a Detroit in the rear and a Lockrite in the front and it did fine. In my personal opinion, a LSD in the back of a rig like yours would'nt be my first choice..........guess it really depends on what you plan to use your truck for. No offense bro, cause I'm right there with ya.....but keep in mind that your rig isn't exactly the "model" street riding machine as it is - look at the sources when you get comments about lockers & etc and ask yourself if those particular individuals use their rigs in the same manner as you do. My F350 has a limited slip in the rear and that works fine for what I do with it (although an ARB would be a helluva lot better than that ****ty LSD when I'm on jobsites

). I would hands down take a LSD over an open diff. If you plan to occasionally run mild off-road stuff and want good street manners from the rear diff then a LSD may be a good option for you....if you built your rig to abuse off road and want maximum traction and don't mind some less than perfect street manners go with a locker.....if you want the best of all worlds buy an ARB or electric locker that is LSD when not engaged (like I believe Auburn & possibly Detroit make).

Just my $.02 - not dogging LSD's at all, especially since I have one in my other truck and very glad that I do, just suggesting that you match your equipment to the intended use of your rig.

rambrush · #3 (**permalink**) 10-03-2007, 07:16 AM

JJC covered things well as usual

I would also vote for a detroit locker in the rear and ARB up front.
I have seen rigs screw themselves right off the road into the ditch with lockers on both ends.

Herbicidal · #4 (**permalink**) 10-03-2007, 08:04 AM

I've been running a PowerTrax rear locker for the last 5 years now and it's finally starting to give up. On the last rear diff fluid change there were some fragments of the internal springs from the locker stuck in the sludge on the drain plug. UhOh!!! I jacked up the rear of the truck by the center diff so both rear wheels were off the ground and spun the left rear. Sometimes both rear wheels would spin in the same direction, sometimes I could 'feel' it unlocking and then only one wheel would spin. NOT normal behavior.

I checked in with my financial advisor (aka the wife

) and later this month I'm going to have Jim at Inchworm Gear set up the rear-end with an ARB RD-129 unit. Not only do I off-road but I tow a 5,600 lb travel trailer, so being able to tow with the locker disengaged will be better for me in the long run.

If you can swing it, go with an ARB.

Oh, yeah you'll need to have an on-board air supply as well.

apimpdad · #5 (**permalink**) 10-03-2007, 10:31 AM

Quote:

Originally Posted by jjc

I ran a Detroit in the back of my '74 Bronco and it was the best locker I've ever owned. They are fine on the road once you get used to driving with one, no different from a No-Slip really. I even drove my Bronco on ice and snow with a Detroit in the rear and a Lockrite in the front and it did fine. In my personal opinion, a LSD in the back of a rig like yours would'nt be my first choice..........guess it really depends on what you plan to use your truck for. No offense bro, cause I'm right there with ya.....but keep in mind that your rig isn't exactly the "model" street riding machine as it is - look at the sources when you get comments about lockers & etc and ask yourself if those particular individuals use their rigs in the same manner as you do. My F350 has a limited slip in the rear and that works fine for what I do with it (although an ARB would be a helluva lot better than that ****ty LSD when I'm on jobsites

). I would hands down take a LSD over an open diff. If you plan to occasionally run mild off-road stuff and want good street manners from the rear diff then a LSD may be a good option for you....if you built your rig to abuse off road and want maximum traction and don't mind some less than perfect street manners go with a locker.....if you want the best of all worlds buy an ARB or electric locker that is LSD when not engaged (like I believe Auburn & possibly Detroit make).

Just my $.02 - not dogging LSD's at all, especially since I have one in my other truck and very glad that I do, just suggesting that you match your equipment to the intended use of your rig.

well the use is for mud, and lots of it. I have been wheeling every weekend for about the past month and a half straight, and im tired of getting stuck

. my friends that have them all use them for mud also, and a few rare trails where i live. all in all they are all satisfied with their limited slips and i have seen them perform. air locker is out of the question, too much money and i dont feel the need to need all of that nice stuff. i use my truck mostly on the road so i dont need anything that might be stressed from driving on the road. So i was looking at either the auburn posi or detroit truetrac for the rear and possibly a power trax lock right for the front. (remember, there arent many choices for the axles that i have)

dyogim · #6 (**permalink**) 10-03-2007, 11:44 AM

I've been running a lockright locker in the rear since 2003. Only issue I had was the pins shearing causing the locker to be engaged 100% of the time. $25 later and some elbow grease, the locker was engaging/disengaging as it's suppose to.

Post SAS, I'm running lock rights in the front and rear. No issues in the front. Only negative is on how hard it is to turn when the front is engaged and you are on an off camber section trying to make a turn. Hydro assist should take care of that.

Ultimately, I'd like to go with a Detroit front and rear but, that requires a bit more money than I can afford right now. So for now, lunch box lockers will do.

As far as the difference between LSD and Lockers. Put it this way. LSD will get you further than an open carrier. A locker will take you even further than an LSD and open carrier.

Imdone · #7 (**permalink**) 10-03-2007, 12:05 PM

Ive been running the Powertrax lunchbox in the rear for the last couple years, has worked out fine, it is a little tricky on the pavement in a turn, but you get used to it and it works out well in the dirt and mud and what not.

jjc · #8 (**permalink**) 10-03-2007, 01:06 PM

If I understand a limited slip's basic operation correctly, they are not going to be nearly as effective in the mud as a locker since both wheels will have very little traction? I imagine a LSD in deep mud will just keep swapping power side to side, which is better than nothing....but a true locker will keep them both spinning full time.

Herbicidal · #9 (**permalink**) 10-03-2007, 01:37 PM

It's possible to "overpower" the limited slip and have it..well...slip! This is because there are clutch packs within the unit. Typically you have to add a special lubricant during rear diff fluid changes for maximum life. And, eventually the clutch packs will wear out and have to be replaced. I have no idea what the life is on those clutch packs, probably varies with use.

apimpdad · #10 (**permalink**) 10-03-2007, 03:49 PM

Quote:

Originally Posted by Herbicidal

It's possible to "overpower" the limited slip and have it..well...slip! This is because there are clutch packs within the unit. Typically you have to add a special lubricant during rear diff fluid changes for maximum life. And, eventually the clutch packs will wear out and have to be replaced. I have no idea what the life is on those clutch packs, probably varies with use.

well what do you think about the detroit truetrac. it doesn't use clutches but gears instead?

Herbicidal · #11 (**permalink**) 10-03-2007, 04:03 PM

Quote:

Originally Posted by apimpdad

well what do you think about the detroit truetrac. it doesn't use clutches but gears instead?

Here's some more info about the TruTrac. Scroll up and down the page for definitions of the various types of lockers and so forth.

This statement from the above link has me a little cautious of this locker:
"TrueTrac differentials require a certain amount of resistance at the ground (i.e. traction) in order to start the torque transfer. A TrueTrac differential may not transfer torque if the spinning wheel is off the ground or on a very slippery surface. If spinning occurs, often a slight application of the brakes, while carefully applying power, will slow the spinning wheel enough to allow the TrueTrac differential to transfer torque to the other wheel."

I know from experience the PowerTrax does not do that. I could get one rear wheel off the ground and the other still drives me forward. I have not had personal experience with the TruTrac to know the accuracy of the above statement.

apimpdad · #12 (**permalink**) 10-03-2007, 04:12 PM

Quote:

Originally Posted by Herbicidal

Here's some more info about the TruTrac. Scroll up and down the page for definitions of the various types of lockers and so forth.

This statement from the above link has me a little cautious of this locker:
"TrueTrac differentials require a certain amount of resistance at the ground (i.e. traction) in order to start the torque transfer. A TrueTrac differential may not transfer torque if the spinning wheel is off the ground or on a very slippery surface. If spinning occurs, often a slight application of the brakes, while carefully applying power, will slow the spinning wheel enough to allow the TrueTrac differential to transfer torque to the other wheel."

I know from experience the PowerTrax does not do that. I could get one rear wheel off the ground and the other still drives me forward. I have not had personal experience with the TruTrac to know the accuracy of the above statement.

thanks for that info, this is probably why no other limited slip has gears like this one. IIRC, they quit making the powertrax for the rear axle on my truck a while ago, and i have also read that they are not good for high horsepower and large tire applications. the only reason i want one for the front is because it would have less stress on it because it wouldn't be engaged all the time. my only other choice for the rear instead of a limited slip would be a detroit, but im just not sure yet.....

Tundra_Hick · #13 (**permalink**) 10-03-2007, 08:39 PM

I find the LSD just starts sliding sideways when its in mud vs power shifting from left to right.

Mine gets a pretty good workout on job sites, I go through a lot of mud in 2wd without any problems.

I was parked sideways on a hill the other day, I put the truck in reverse in 4wd, putting the rear higher up the hill, so I could drive forwards down the hill. The rear end wanted to slide sideways while the front end pushed me up the hill. If I didn't have 4wd, I wouldn't have gone anywhere.

I do find that in a tight circle, if I goose the throttle too much, I get wheel chirp. Also on snow or ice I slide side to side in 2wd.

Hugemoose · #14 (**permalink**) 10-03-2007, 10:53 PM

Quote:

Originally Posted by apimpdad

thanks for that info, this is probably why no other limited slip has gears like this one. IIRC, they quit making the powertrax for the rear axle on my truck a while ago, and i have also read that they are not good for high horsepower and large tire applications. the only reason i want one for the front is because it would have less stress on it because it wouldn't be engaged all the time. my only other choice for the rear instead of a limited slip would be a detroit, but im just not sure yet.....

I have heard the same thing about the No-slips regarding larger tires and the increased stress. But I don't have that problem; probably never will!

It is a shame that you have very limited options. I would personally recommend a locker for you though. An LSD really is great, but just isn't made for severe mud which you said you run nearly every weekend. Now you did say your buddies made it through stuff just fine, and I don't doubt that. What I would worry about is the wear they are doing to the LSD.

If you put lockers in, there's simply nothing to worry about when you're in the mud. All 4 wheels spin with FULL power. There is no middle man (the clutches) to try to spread out the power. All in all I think it would be better and you'll be glad you have the lockers when your buddies get stuck

This is of course if you can live with the driving adjustment you'll need to make with the lockers. I still don't like driving in the rain with my rear locker. It's just a pain when I have no choice but to power into a turn and that inside tires just chirps away

apimpdad · #15 (**permalink**) 10-03-2007, 10:55 PM

well y'all are making me second guess about getting a locker! i knew i shouldn't have asked.

well i will probably be looking at the detroit again and looking for reviews. I am just worried about the on road performance, i have heard that they aren't very good for towing. what do you guys think?