Hypothetical question. I currently have an open diff in the front and an Aussie automatic (lunchbox) locker in the rear. My rig is a weekend warrior, light to medium wheeling, expo rig on 31s. I occasionally drive it back and forth to work when my Civic is low on gas (hardly ever) or when the mood strikes me. The rig is an AX15. I'm honestly starting to get sick of the Aussie constantly locking/unlocking and bucking at slower speeds (in parking lots I usually have to clutch in to make it stop). I do however, like the Aussie offroad and when I feel like being a hooligan and do donuts/drifts.

My idea is to replace the lunchbox with an aftermarket, clutch type limited slip like the Dana Spicer, Auburn, or Detroit TrueTrac to improve my street ability while maintaining that rear wheel drive not open diff feel and put in an automatic lunchbox (i.e. another Aussie) locker in the front for when I hit the trails.

My questions are:

1. Is this stupid?
2. Do automatic lockers in the front really only engage when in 4wd i.e. torque is applied?
3. What part does the AX15 play in all of this?
4. Has anyone done this?

 

Stupid is a matter of opinion.

Yes automatic lockers when in the front only engage when torque is applied, if not you couldn't steer to save your life if it engaged all the time.

It's a transmission....

I have a friend who rocks a lunchbox lockers both front and rear. He's 7 inches of lift and 35s. It's his DD and play toy on the weekend. Pretty much anything you can conceive has been done to the XJ

 

Many people do that. It is a very solid setup. And yes, lunchboxes in the front only engage in 4wd.

 

1. No, this is a good setup IMO

2. Yes, the auto locker up front only becomes a factor in 4WD or during super tight turns (AKA parking lot)

3. The AX-15 is fine, the LSD makes things so much better in the rear from both an offroad and daily driver perspective.

4. This is the setup I have now, Aussie up front with an LSD in the rear. I think there are few circumstances I've encountered where the limited slip being not 100% locked was a shortcoming, and the Aussie up front has helped immensely offroad.

The downside to your idea is that a new limited slip is pretty expensive, and for that price it may be worth it to shell out a couple hundred extra for a selectable locker.

 

When my xj was my dd I only had the front locked and I loved it. Practically invisible in 2wd and did great off-road. Now my jeep gets driven once a week and locked with Aussies both front and rear. I feel you when it comes to the bucking. It's kind of annoying when it starts doing it in 2-3rd gear going around a long swooping turn. Clutch in and hold on is all you can do.

Being mainly a off-road rig I deal with it though because having full lockers off-road is amazing. You can swap your Aussie out for a limited slip in the rear for better street ability but you will be sacrificing off-road performance. It really boils down to what you think is better for you. For me off-road performance trumpeted daily drivability. I wouldn't call it a stupid move though since a limited slip is still better than open diffs. I think a front locker with limited slip would give you the best of both worlds.

 

Thank you guys for the insight!!! Keep it coming. I'm liking this idea.

Haha, exactly! I'm glad you understand.

 

If you're going to get a limited in the rear to replace the Aussie then do 2 things... first: Get the truetrac it's the best one and has no wearable parts. Second: Sell me the aussie locker! If you're looking to sell it in the future i'll look out for it. I personally want to do the opposite and run an aussie in the rear with a truetrac up front, I have a NP242 and want to keep the full-time option.

 

yes to this

 

to swap out to lsd in the rear, you will need a new carrier, therefor you will need a gear setup along with that lsd. getting pricey now.

keep and deal with the locker in the rear and get a lunchbox in the front. cheapest option.

best option, get selectables.

 

Unless I find someone local with a Truetrac 8.25 who wants to trade, the Aussie is yours.

Good point on the price. Those Truetrac's aren't cheap by themselves either.

I don't really want two lunchboxes as the rig's number one priority isn't wheeling. If it was, it wouldn't be on 31s... Same is the case with selectables. The idea behind the limited slip is to have that driving feel on the street with a "proper diff." As unrefined as the Aussie is, I would NEVER go back to an open diff and as far as I gather, the selectable operates as such when not on (probably the most obvious thing I've said today )

 

If you purchase a used auto-locker, I strongly suggest new pin springs. They may look fine but are often compromised when removing them from locker and from previous use. Aussie/Lokka springs are $20

 

I run Detroit Lockers front and rear but you would never know the rear one was there is no noise with it and 100% reliable. Buy quality the first time and never look back...........BTW forget the LSD they suck when you need them most.

 

The LS rear setup is very good especially on snow or ice. Since you have the 8.25 rear, you might be able to find someone willing to part with a stock 8.25 LS. Good luck and have fun.

 

This is the setup I decided on after a lot of research, but it's not completely installed yet.

I went powertrax no slip (not lock right) in my HP30 in the front and 8.8 with stock LSD in the rear. I LOVE the LSD on the road and I'm hoping that since I went the more expensive route on the lunchbox up front that it'll be invisible. If it's good enough, I might go powertrax no slip in the rear too.

So far my rear axle is swapped and my front is being built. Doing steering, truss and brakes while I have a donor.

 

I guess the moral of my story is, consider the 8.8 swap. You'll get LSD, a stronger axle (not that you need it on 31s) and disc brakes on 1 fell swoop.