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J1R3D 02-14-2010 09:20 PM

Recently a friend of mine mentioned putting lockers on the Jeep to help when doing some offroading, and I was wondering if anybody could give me some more information on this topic. From what I was reading with the lockers engaged, you cannot steer. Any information given would be appreciated

s3nt3nc3d 02-14-2010 09:29 PM

You can steer, but it won't be as easy to's going to fight you a lot on turns. But typically when you're using 4wd, you're in a situation where you either are going to be going straight or if you are turning, your wheels should slip enough to make the turn.

Jerry I'm sure will chime in with more detailed info I'm sure...this seems to be his specialty. lol

J1R3D 02-14-2010 09:34 PM

see that is what i was thinking. my father was against it for the steering problem, but if i am stuck, i dont think im worried about steering at the moment. one thing i was thinking was if it is possible to just put the lockers on the back wheels, to leave the front open for full steering capability

s3nt3nc3d 02-14-2010 09:40 PM

You can put lockers on the back... I've read that many prefer to do it to the front since they'll only be locked when you're in 4wd (and Jeeps aren't designed to be driven in 4wd with standard road conditions).

If you get a good set of lockers, front or rear, I believe most good ones are designed to be open until a wheel breaks free and starts to lose traction...I'm not the most knowledgeable when it comes to that stuff though so I'm not about to try going into detail.

J1R3D 02-14-2010 09:51 PM

Yes, from what I ad read it wasnt for regular driving, from my understanding they could be controlled to be on or off? Like I said, not to sure, but willin to learn

jdhallissey 02-14-2010 09:52 PM

First thing is first what axles do you have? IF you have the dana 35 DO NOT LOCK IT unless you want to toss 1500 at it and still not have it to a point were you have to worry bout it. As for locking the front, depending on the money depending on the 4 wheel drive conditions you have on the highway I would say no-slip aussie the front and if you have a dana 44 in the rear I would say a aussie there too.

The thing about lockers is how much do you want to spend. I have dana 44's under my jeep and chromo's front and rear (air lockers). If you can spend 3k I would do the 30 spline rear with a arb and a 30 spline front arb and then you can do just about anything in the jeep without worrying about your axles.

It is about money:punk:

J1R3D 02-14-2010 09:56 PM

Well, I am not exactly sure how to find out what type of axles I have. How can i go about figuring that out? And money isnt so much a problem, by the time I would actually take the time to purchase and what not, I would have plenty to spend.

s3nt3nc3d 02-14-2010 10:06 PM


Originally Posted by J1R3D (Post 546187)
Well, I am not exactly sure how to find out what type of axles I have. How can i go about figuring that out? And money isnt so much a problem, by the time I would actually take the time to purchase and what not, I would have plenty to spend.

Crawl under the rear of the Jeep...if you have a metal filler plug in the rear differential, it's the Dana 44 rear. If it's a rubber/plastic plug, it's the Dana 35.

J1R3D 02-14-2010 10:09 PM

well as soon as i get somewhere dry and not parked in snow i will check, which will be in the morning ha.

jdhallissey 02-14-2010 10:21 PM

Honestly I would lock the front with a power trax no slip. Then I am 99 percent sure that you have a dana 35 in the rear. Save up and change it with a dana 44 and a detroit or power trax too :punk:

oshauno 02-14-2010 10:30 PM

I would suggest a selectible locker front or rear. They you can just lock it when you need to.

oshauno 02-14-2010 10:38 PM

randys ring and pinion is selling ox cable lockers at cost right now. i dont they have many left in stock but heres the link if youre interested. OT OXM35-4-27 - SELECTABLE LOCKER,LOCKER,XJ,DIFFERENTIAL,TJ,MODEL 35,JEEP - OX Locker by OX USA for Model 35 with 27 spline axles. Fits 3.54 and up. The OX Locker uses a cable to engage and disengage the unit. When the unit is disengaged it is a stan

Jerry Bransford 02-15-2010 12:54 AM

I have automatic lockers front and rear on my Jeep and steering is only mildly affected offroad when the turns get really tight & twisty. Otherwise I have no issues with steering at all. Here's copy of a writeup I did on locker several years ago, sorry it's so wordy...

Here's something I wrote years ago that was recently revived on another forum... I thought it might be useful here too.

Q: Why do we need lockers, I thought I had four wheel drive??

A: We need lockers for tough terrain because the differentials installed into most of our front and rear axles have a characteristic that can turn our 4x4 Jeeps into 4x2 Jeeps in tough traction situations.

A factory differential (sometimes called an "open differential") has a characteristic in that when one wheel loses traction, that wheel will start spinning ineffectively. You've seen that happen before, I'm sure. The bigger problem is that one spinning wheel on an axle causes both wheels to seem like they have very little traction... so even though the wheel on the other non-spinning side may have excellent traction, that non-spinning wheel won't receive enough power to keep you moving. Why? Because the differential screws up and only "sends power" to the wheel that is spinning. That is not technically totally accurate but it illustrates the problem very nicely, with a more technically accurate explanation as follows.

So the engine, via the drive shaft and differential, is seeing very little resistance from the axle with the spinning tire. So what? If the engine sees little resistance, it develops little torque. Low resistance to the engine, low developed torque. Lots of resistance to the engine causes it to develop lots of torque. Connect a dynamometer to an engine without a load on it and it'll show very little developed torque. Now put a brake of some kind against the engine output shaft (to add resistance) and the amount of torque developed by the engine will suddenly and dramatically rise. No resistance, very little developed torque... high resistance, a high amount of developed torque.

When a wheel starts spinning, the reduced resistance the engine sees from the axle causes the engine to dramatically reduce the torque it sends to the axle. Here's what else is going on that is a key to understanding this whole thing... a stock factory differential ALWAYS ALWAYS ALWAYS splits the torque it receives from the engine 50:50 to each wheel. Exactly 50-50, every time. So when one wheel is spinning and the engine torque decreases dramatically because of that, the OTHER wheel that still has good traction is seeing 50% of the greatly reduced torque. In fact, the torque sent to the axle is reduced so greatly that when the differential divides it 50-50, there is insufficient torque for the wheel with good traction to keep you moving. This means you're stuck!

So when you're driving on a dry paved road, both tires are receiving equal amounts of power and the high traction they're seeing from the dry road helps the engine to develop maximum torque. Both tires are pushing equally with lots of available torque. Now jack up a wheel (or lift it with a rock on a trail you just drove over) and you're not going to move even though the other tire is still on the ground. The tire in the air is spinning like crazy, causing the torque that axle receives from the engine to go right into the toilet.

So, when one tire on the axle is spinning, you don't have enough power for the other tire to keep you moving. For obvious reasons, all this is a huge problem for a 2wd vehicle (just one axle to drive you). It works exactly the same for a 4x4 but you have one more axle to assist in keeping you moving. But if one tire per axle has poor traction, you are stuck... since one spinning tire per axle is enough to reduce all developed torque from the engine down below the point the Jeep needs to move forward.

OK, we know what the problem is now, what's the fix? One, you could STEP ON THE BRAKES a little... which would stop the tire(s) from spinning so more torque would be developed, which should be enough for the OTHER tire that still has good traction to get you moving again. Stepping on the brakes forces the engine to work harder so it develops more torque which is sent to the wheels... so that gets more torque sent to the wheel (both actually) that still has traction so you may be able to get unstuck. Yes, stepping on the brakes (to a point best learned by practice) works rather well in these situations. Just about all drivers used to know that technique when few roads were paved... but it's just about a lost art now.

So what does a locker do? It mechanically LOCKS the left and right wheel together to overcome the above problems. It won't allow one wheel to start spinning while the other sits doing nothing. The left and right wheels are mechanically locked together.

Automatic lockers keep the left and right sides locked together except when you turn left or right, where it will automatically unlock the outside wheel during the turn until after the turn is completed at which time it locks up again. When the locker unlocks for a turn, the outside wheel is allowed to rotate faster than the inside wheel so it doesn't hop and skip during the turn. The inside wheel is driving during a turn with an automatic locker-equipped vehicle. The locker automatically locks again once both wheels are turning at the same RPMs again.

The problem with an automatic locker is that most are not very street friendly when installed in the rear axle. Because they keep the left and right wheels locked together except when forced to unlock for a turn, they can cause unusual handling characteristics like rear-end waggle, tire chirping, disconcerting loud bangs and snaps from the locker, and even sideways sliding down slippery off-camber slopes where they earned the nickname "low-side finder"... which can sometimes produce a high 'pucker-factor' at times. For offroading however, locker's negatives are far outweighed by their benefits in challenging conditions.

But in many Jeeps like the TJ, an automatic locker is fine when installed in the front axle. Since the front axle doesn't receive torque in 2wd, a front automatic locker unlocks easily enough for turns that you may not even notice its presence. Only in 4x4 is the front axle receiving torque which makes it harder for the locker to unlock for turns. About the only conditions where an automatic front locker would not be good in the type of 4x4 system a Wrangler TJ has would be on icy or snow-covered roads where you need 4x4. In 4x4, a front automatic locker would cause understeer (make the Jeep want to drive straight in a turn) which would not be good if the road was slick from snow or ice.

A manual locker is "open" (unlocked) until you actuate it. The ARB Air Locker and the cable-actuated Ox-Locker are examples of manual lockers. These are good because they remain unlocked until you choose to lock them. This eliminates the handling problems automatic lockers have on the streets.

By the way, a locker is installed inside the differential and it replaces the "spider" gears that make a differential work they way it does.

So some Jeepers add lockers in the rear, others add them to the front. I happen to think locking the rear axle first does the most good, but I have installed automatic lockers into both of my axles... which works pretty darned well. But if your rear axle is the notoriously weak Dana 35c that comes stock on all Wranglers except the Rubicon and Unlimited, avoid installing a locker in the rear axle and install it in the front axle instead. Since the front axle rarely receives more than 50% of the torque that the rear axle does, it can usually handle a locker without problem with reasonably sized tires. But if your rear axle is the optional and far stronger Dana 44, by all means install a locker into it if your trails are tough enough to make a locker desirable.

So what's a limited slip differential? First, it is not the same as a locker. It is more or less an automatic brake for the spinning tire... it performs kind of like when you use the step-on-the-brakes technique so the spinning side gets coupled to the non-spinning side for more resistance so more engine torque can be generated so the non-spinning tire receives more torque from the engine to help get you moving again. It operates as a brake somewhat by coupling the added resistance of the side with more traction/resistance to the side that has less traction/resistance. A LSD depends on some tire spin to get it working so it's not as efficient for challenging terrain as a locker is. But then generally speaking, a LSD is far more "driver friendly" on the streets, which is why we all don't just have lockers in our Jeeps.

Hope this helps a little.

jcf 02-15-2010 01:57 AM

I have air lockers front & rear, If I engage all 4 the steering is a little heavy up front but not really a problem. Sometimes it only takes the rear to be locked & it will crawl up no problems. I have 35 inch tyres & really love having the lockers, they have got me out of spots that I definately would have gotten stuck in without them. Today I had to pull my son up a hill in the snow, backwards, my Jeep hardly even skidded dragging his S10 with just my rear ones engaged. They are well worth spending the $

J1R3D 02-15-2010 12:47 PM

i was thinking about maybe going with air lockers. from what i was reading, and from what some others I know mentioned, it sounds like one of the best ways for me to go at the moment.

Jerry Bransford 02-15-2010 01:10 PM

ARB's air lockers are probably the most respected selectable locker going, you can't go wrong with them at all. Do choose your installer carefully though, be sure to find one that specializes in and has plenty of experience installing ARB's air lockers. The key to their reliability is in the installer's attention to detail and quality of his work, even more so than any other locker.

J1R3D 02-15-2010 01:16 PM

hhmm, now i am thinking twice, I was going to be the installer :eek:

jcf 02-15-2010 01:16 PM

That is very true Jerry, I agree 100%. A bad installer can mean air leaks in the lines & all sorts of problems

J1R3D 02-15-2010 01:52 PM

is it a hard install? i mean i would have help if i was doing it, but i wasnt sure how indepth the installaion could be

Jerry Bransford 02-15-2010 02:12 PM

Don't even consider installing an ARB locker on your own. First, it involves removing the old carrier and replacing it with the full-case ARB air locker. That then requires you set the backlash between the ring & pinion gears by shimming the ARB case left/right until you get the original amount of backlash you had.

Then the rest of it isn't easy either, the bearing cap has to be drilled, the axle housing has to be drilled & tapped, and it doesn't get any easier from there wiring the control switch, relay, and installing the electrically actuated air control solenoid.

Don't even consider this particular installation, it's nothing like installing a simple lunchbox locker like an Aussie or Lockright.

J1R3D 02-15-2010 02:24 PM

oh man...looks like ill be looking around for someone to do it then, and to my knowledge there isnt anybody in my area

Jerry Bransford 02-15-2010 02:54 PM

Contact ARB, they can tell you the nearest shop to you that is capable of installing it.

J1R3D 02-15-2010 03:50 PM

ok, i will check into that. i appreciate all the help from everyone

J1R3D 02-15-2010 07:35 PM

Jerry, in the one post, you mentioned limited slip differential...could you possibly give me a bit more information on that

Jerry Bransford 02-15-2010 08:00 PM


Originally Posted by J1R3D (Post 547132)
Jerry, in the one post, you mentioned limited slip differential...could you possibly give me a bit more information on that

Do you need more than what is in the last paragraph of post #13 above?

J1R3D 02-15-2010 08:08 PM

If possible, im not sure if there is more information, but the LSD might be the way I go for right now.

Jerry Bransford 02-15-2010 10:19 PM

What do you need it for? Street use only? Street and trail? Combination? What type of conditions do you get in where you feel the need for an LSD or perhaps a locker? Do you need 4x4 to get around during the winter where you live?

J1R3D 02-16-2010 02:13 PM

I am looking for a combination. Right now I have just been street driving, I just got the jeep, but I do wanna start trailing. And also where I live i need the 4x4 in the winter. I just feel having the LSD or lockers would help when I start trailing, and in really bad winters, like this recent one I have had.

dj_chizzle 02-16-2010 02:32 PM


Originally Posted by Jerry Bransford (Post 546348)
Hope this helps a little.

That was way informative Jerry, thanks! :wavey:

Jerry Bransford 02-16-2010 02:37 PM


Originally Posted by J1R3D (Post 547808)
I am looking for a combination. Right now I have just been street driving, I just got the jeep, but I do wanna start trailing. And also where I live i need the 4x4 in the winter. I just feel having the LSD or lockers would help when I start trailing, and in really bad winters, like this recent one I have had.

From that, it sounds like a Detroit Truetrac limited slip differential in the rear would be great. I used to run them front and rear and they are great on the street and helpful in most trail conditions.

The Detroit Truetrac is superb on slick streets and does not cause any steering or handling issues. That it is near bulletproof is another good thing about it. :)

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