Very interesting. It has been my experience that the back brakes always last at least twice as long as the front brakes. That is with front wheel drive, rear wheel drive, and 4 wheel drive vehicles. The only thing is that they all had rear drums. I also remember people posting here where their Vibe did not need brakes for 80k plus, and the rears still looked good. They were rear drums too. Probably mostly highway drivers. Might not have traction or stability control either. I see all the time where Prius' go forever without needing brake changes, but then again they have that brake regeneration thing going for battery power and use ceramic pads.
One thing to note on at least the 09-10 Vibes is that the stock OEM front pads were a ceramic mix, wheras the rears were the more traditional semi-metalic, if memory serves me.
I just do not see stability control wearing the rears down that quickly, unless you are always trying to hang it out there and always have a flashing yellow light coming on in the dash. Possibly more wear for fronts if driving and taking off in icy and snowy conditions, but I was under the impression that traction control is more of an electronic, throttle/timing thing that cuts power first, then uses brakes if still needed.
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2010 Vibe 1.8 auto, fwd, base, air, preferred package, cargo mgt, cargo cover, ultra white.