Differential Upgrades

So I want to know; would it make sense to have a locker in the front and LSD in the back? That way turning in 2wd wouldn't be a problem, but in 4wd have better traction?

 

Budget is definitely a big thing to me, and selectable lockers are quite spendy.

 

I run a Detroit Locker in my rear axle and an Eaton TruTrac in the front. I did not want to worry about the added complexity of air lines or wiring, and while ARB’s are really good lockers I have seen a good amount of jeeps troubleshooting leaking air connections on the side of the trail.

The newer Detroit lockers have been improved a lot over the old school design where the loud pops and bangs on the street are almost nonexistent. I drive my jeep on the highway fairly often without any noticeable affects from the detroit in the rear. The only time I do notice it is under a hard shift or slow, tight turns in a parking lot. The rear locker does not really affect turning at all, but the front will definitely add some resistance. If you have power steering you probably won’t notice anything but when I had manual steering it was an arm wrestling match in 4lo.

 

Depends if you ever plan on using the Jeep on ice or snow packed roads. Either of those options in the front axle pretty much eliminates 4x4 use in those conditions---assuming you want to actually stay on the said road. Even on the trail, having the front axle locked makes steering much more interesting. I've become very fond of selectables at both ends and engage them only when needed.

 

I put an OX locker in the rear axle, front axle is still open. When the rear is locked the jeep does well on muddy roads even in 2wd. Pretty fun actually.
Eventually I would like a selectable in front, but there are no selectable lockers made for the Dana 20 series, so an NT dana 30 is on my wish list.

 

I agree with many comments above. Locker in the rear; if street driving an LSD in the front, if mostly off-roading a selectable locker. I have a Detroit in the rear of my Nissan, used to have an LSD. Driving in snow was not dangerous like some would say; common-sense driving was fine. Ice is a different story. The LSD in the front was great. Later when I built up the truck and changed axles I put another Detroit in the rear and an ARB selectable in the front. Works great. My Blazer has a Lock-Rite in the rear and an open front, that drives fine.

I have LSDs for both axles to put in my CJ when I get to that step in the project. I will not be off-roading it but want better traction than open differentials.

 

You already have a TrueTrac in your front axle, from your other post. Is your rear axle open? What do you want from this Jeep? How experienced are you?

A large fraction of these Jeeps came from the factory with a LSD at the rear and an open front. You can go lots of places with this combo. Supposedly the TrueTrac is a very good LSD, and would be a nice upgrade for your rear axle if not so equipped. The factory option from that era was the Dana PowrLock, which also functions well and is strong and durable.

How much will you drive on the street? A locker (and even an aggressive LSD) can behave unpredictable on slick surfaces (ie ice). Is NE Nebraska or New England? Either location will see ice on the roads in the snow season. If you can park the Jeep in the winter, I'd think a lunch box locker for the rear would be a good choice, to go with your LSD in the front. If you're going to drive on the winter streets, an LSD in the rear and leave the front hubs unlocked might be your best option.

 

It looks like you’re running stock axles. Keep in mind that this will limit your options withou major work and spending. You will be able to find a Power Lok to fit the rear 19 spline shafts, probably a Detroit locker and there are lunch box lockers as noted above. There are no new selectable options without upgrading to 30 spline shafts, which is likely easiest done with Herms Full Floater kit (this would get expensive). ARB did make a 19 spline D44 unit but they are hard to find.

A Power Lok could probably be found for the front as well.
I’m a fan of the Power Lok. They are easy to rebuild, strong, reliable and easy to tune to a desired tightness. For all but the most demanding 4 wheeling, they perform really well.
I’m running ARBs front and rear now and like having the open-open option. But I did really like the Power Loks. Also I have power steering, so that probably makes a noticeable difference when locked in the front.

 

On the bay
Dana 27 front axle NOS Power lock Diff carrier 22480X Fits Willys Kaiser jeeps

Did manage to destroy my Dana 44 Power lock, changed to a 57 Pontiac rear with a spring assisted LS, when I had my ‘63 M38A1 ( bought in auction at Camp Pendleton MC). It also had a Power lock in front - great for dunes!

Both worked great until I abused them ( a lot) with my V8 and Tru Trac tires (32” if I remember correctly)

 

Spool in the back and lock right in the front. That's cheap and it works. I had a zuk with lock right lockers in the front and rear.

 

A locker in the front can cause terrible under steer in slippery conditions like ice, snow, slick mud, loose sand, etc. something to consider.

 

The OX locker is definitely a sweet unit!

 

My experience in this area isn't in a CJ but multiple XJs. I've ran locked front, locked rear, and locked both ends. Each time has been on a budget so selectable haven't even been considered, in fact one of my XJs I "Lincoln locked" in the rear. All of these Jeeps have been daily drivers. My favorite budget daily driver setup has been a lunchbox in the front axle and an open rear. I wouldn't mind putting a gear driven limited slip in the rear of my current XJ though. Never had any issues off pavement having the front locked up. I've only driven on ice/snow a few times (we don't get much in north central Texas) with the setup and didn't have any issues either. Just slowed way down.

 

Surely everyone is familiar with Rango? Brennan Metcalf's flatty with no lift and 35's? He prefers the automatic locker in the front and a LSD in the rear. I have TruTrac in front of my M38A1 with a Lockright in the rear. My '75 CJ-5 has PowerTrax No-Slips in both ends, and I have a '74 CJ-6 I just picked up that has TruTracs in both ends. No doubt if mud and sand and the street are 90% of what you do like me, the TruTracs are almost invisible on the road and the only front axle traction device recommended for full time four wheel drive ala Quadratrac.

 

X2 If you can afford it.

I really like my Dual ARB's. My uncle loves his ARB up front and True Trac in the back. Steve had True Trac's front/rear and easily succumbs to the dreaded lack of loading/tire in the air issues.

 

Just like a Powerlock some brake manipulation can help with this.

 

This is true. But when your all twisted up, looking down Cadillac hill..... easier said than done