ARB is a good choice, but there are other diff choices you can consider. First of all, you need a selectable locker in a JK axle. The ESC (Electronic Stability Control) system does not work well with automatic lockers, like the Detroit, and other ltd-slip devices.
I have a JK with a Detroit locker. The device works excellent off road, but you WILL get lots of ESC events, and kicked into limp mode with any automatic (non-selectable) device. Without a selectable locker, you will need to remember to hit the ESC button EVERY time you start the car. Trust me, you will forget, and find yourself in limp mode frequently.
The other selectable locker choices are the Eaton E-locker, and the OX Locker. I do not recommend ANY of the imported Chinese knockoff diff’s that are advertised. You get what you pay for, and even less on imported knockoff products.
Eaton just released a new and improved E-locker for the 44’s. E-Lockers use electric actuation. Can’t vouch for it yet, but looks promising. The older E-lockers had 2 spider gears, and we felt our customers needed more. Therefore we have not recommended them in the past. Dynatrac seriously stands behind our warranty, and advocates for our customers. We do not want to get stuck in the middle of a diff warranty dispute, and will only work with partners that take their warranties as serious as we do.
The OX device is very strong and easily rivals the ARB durability. It is made in USA, whereas the ARB is not. It can be had with electric actuation. We are getting good feedback from customers using this device. OX also has versions for our ProRock line of axles. The device includes their special diff cover, since that is where the connection takes place.
We have had very good success with ARB, and also have a good relationship with them. I have never had them decline any of the very few warranty claims through Dynatrac. We have installed thousands of ARB’s.
All selectable lockers have some kind of line, be it wire or airline. Properly routing the line is mission critical, and it amazes me how little thinking some folks put into this task. Every car is different. You have to think about all the ways the axle moves and anticipate interference with branches, rock, mud, etc. This is more easily achieved with wire than an airline, because of the size and flexibility of wire. Wire is also less susceptible to melting, but will melt and short out if it contacts exhaust system parts. Both wire and airline can be cut or chaffed into failure.