Front locker.

[Screeper]

I have had ARB"s front and rear in other vehicles and it worked alright. That was before Eaton came in with their version. Today I would go with Eaton without hesitation. The ARB was not completely dependable as there is alot to break and it often developed leaks and compressor problems. Never broke one inside the diff though and it was always driveway repairable. I also would like to think there has to be a way to wire the Eaton in to the rear locker so it could only be turned on second to the rear locker (stereo shop?). I know thats how they did it with my ARB's. I never had an occasion to lock my front and leave the rear open. I think that is just asking for breakage. Hope the info helps