Jeep Locker Overview - Locker Lowdown

Street:
You'll think you're driving an open diff. The Trac-Lok is largely unnoticeable.

Off-road:
You'll think you're driving an open diff. The Trac-Lok is largely unnoticeable. Unless it's new from the factory, don't expect anything but poor performance off-road from a Trac-Lok.

Good: It probably came in your Jeep from the factory. The unit can be rebuilt at home.

Bad: They require gear oil with a friction modifier and have wearable clutches inside. If you're planning on adding a lunchbox locker, you'll need to order a special application that will work with the clutch disc recess in the case. The recess inside of the case makes it slightly weaker than a standard open diff case. It's difficult to weld into a spool if that's your thing. Basically, they don't work well, so don't waste your money. You're better off with an open diff.

Street:
A spool is noticeable on the street when cornering sharply, but is very predictable, and we actually prefer one in the rear of a short-wheelbase vehicle over an automatic locker. Since there's never any loading or unloading, you don't get the jerking or banging associated with automatic lockers. It will increase your turning radius somewhat, and you'll notice your rear tires will scrub and chirp around corners.

Off-road:
Since a spool never unlocks, it's extremely predictable off-road. And since it's a solid chunk of metal, we've never been able to harm one. We haven't really found the loss of turning radius to be a hindrance. That's what Reverse is for. We hypothesize that a spool is actually easier on axleshafts off-road because there's never any sudden loading or unloading. Power is always evenly distributed to both shafts, and traction is generally phenomenal.

Good: Inexpensive, simple, lightweight, and strong.

Bad: Tires will chirp when turning on pavement, tire wear is increased, and the turning radius increased. Really only for a rear-axle application that's primarily used off-road.

Street:
Overall, the welded diff will behave just like a spool. In some instances where the axleshafts are of a smaller diameter (1.30-inch and smaller), there may be some torsional loading and unloading of the axleshafts when used with sticky tires. This will make for more tire squeal and chirping when turning. Basically, the welded diff loses a point to the spool because of the potential for the welds to break, not due to any difference in performance.

Again, it loses a point to the spool because of the potential for failure, but as long as your welds hold, you're good to go. Like a spool, we wouldn't recommend a welded diff for a front application. We pulled our welded Trac-Lok apart after about 30,000 road and trail miles and found that a crack was beginning to develop in a weld near the side of the case. Left alone, the weld could fail, sending chunks of diff into the gears and bearings. So if you decide to run a welded diff, plan on checking it frequently.

Good: Dirt cheap and gives great traction.

Bad: It's pretty butch, and the finished product will only be as good as your welds and the strength of the stock case. It's really only good for some rear-axle applications that are used primarily off-road.