Everyone is missing the biggest selling point for the E-Locker, It's the strongest 8" third members Toyota has ever made.
See, in order to fit the locking mechanism of the e-locker inside of the 8" diff, Toyota had to use an enormous carrier bearing, so not only is the operation of the e-locker better and more reliable than the ARB, it is also the strongest differential available.
I have heard about e-lockers taking time to engage and disengage, but mine has never taken longer than about 3 seconds to work.
As for ARBs, I grew up wheeling Marlin's truck, and his front ARB air locker would sometimes not unlock for up to 20 or 30 feet of driving while turning a corner. And you know what? I'm sure this is the same with a e-locker. If the diff is in a bind, then it shouldn't matter what kind of locker you have, it will take time for it to disengage because you'll have to wait for the load to be settled by rolling on flat, straight ground...
I will take a Toyota E-Locker any day hands down no compromise no questions asked right away today where is one in a heart beat over an ARB immediately.
In addition, E-Lockers are much much cheaper than ARBs. You can pick up a good used e-locker for around $400, and about $70 for a cable setup or about $20 for a couple relays and wires if you wire it up. And that's it, you are done. But an ARB is like $600, then you still need to get an on board air compressor, there's another $200?
I've been on a snow run and seen an ARB stop working because it got to cold. And I've seen an ARB air line get to close to an exhaust and melt in two leaking air... And if an e-locker was cabled wrong or wired wrong, Whitey and the others are right, two 12mm bolts and the motor comes off, and with a screwdriver, the locker can be engaged or disengaged....
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