A “locker” is a traction-aiding device that provides power to both wheels regardless of traction.
Locking hubs allow the wheels to be “disconnected” from the axle shafts so that the gears and driveshaft do not spin while in 2WD. They do nothing to help traction, but will reduce wear and tear on some parts and maybe increase gas mileage a little.
One nice advantage to the Warn kit is that if done right (high quality axle shafts and Ox or CTM u-joints), the hub becomes the weak point and will break before the axle shaft/u-joint. With the “small hub” Warn kit, changing the hub only requires removing the wheel, and the hubs are less expensive and take up less space than spare axle shafts. I'm looking at this option pretty closely….just need the $$$ now.
I have the same locker in mine and haven't had any problems with it. A friend is running 35's on his D30 with one and also has not had a problem. They seem to hold up pretty well in front axle applications. If you do have a problem then upgrage to a Detroit/ARB/Ox, but why spend the money if you don't need to?
The big problem I've seen with the vacuum disco axles is that they sometimes don't want to engage, usually due to a broken vacuum line or faulty switch…..and it's usually at the worst possible time. You can get a cable operated mechanism to replace the vacuum disconnect if that becomes an issue.
Actually, the decision as to what kind of locker to get was not actually made until the work order was being filled out at the 4×4 shop. I had narrowed it down to either the Detroit or an ARB. I couldn't make up my mind. Both are great lockers….but which one should I get? Money wasn't the main driving force since I already had a QuickAir 2 installed in the TJ. With that out of the way, it was only a couple of hundred dollars difference between the cost of the two lockers. Considering everything that I was having done (I was getting new BFG MTs and new alloy rims too), this was less than the tax I was going to be paying.
As I stood at the counter, making comments on what I wanted included in the work order, we got to the locker. I said, “Why don't you figure up the price of an ARB and one for the Detroit and I'll see which one looks better.” Little did the guy know I was still struggling with which locker to get. He started on the ARB first….”let me see….one locker, one spare solenoid, a spare fuse….”. “Wait a minute”, I said. “What's with all of this spare parts stuff? I asked you for an ARB price workup, not your spare parts inventory.”
The guy at the counter, with a little smirk on his face, looked up at me and said “Do you actually plan on going off-road without spare parts for your ARB?” That was it….my mind was made up. Probably not the most scientific way of doing it, but I thought it beat the heck out of tossing a coin. I will admit that good 'ol Murphy (the guy in Murphy's Law) does seem to follow Jeepers around on the trail. I figured that the less parts I have to make my locker work, the better off I would be.
http://www.stu-offroad.com/misc/locker-1.htm
”….People make out full lockers to be some sort of evil handling demon that will throw your truck off a cliff at the first opportunity. I've had mine in for about 30,000 miles now, and other than an occasional “Ka-POW!” sound (usually while backing up) and increased axle wrap before I put on the torque bar (now slight wheelslip - mini burner - on polished concrete or slick asphalt at low speeds), the thing is transparent. I wouldn't even know it was there, except I almost never use 4 wheel now. It's been to Tahoe, Oregon, Mexico, Arizona, Nevada, etc., and no problems, nothing unusual. So full lockers are not the Devil's own street-handling device in my case.”