If it was me I'd much rather continue replacing front pads and rotors into the future than add all that wear to the tranny, it even says in the car's manual not to use the tranny as an engine brake, it causes additional wear and heat buildup. A tranny costs WAY more than brakes......pads are like $30 a set for the front....and the rotors maybe $50apeice? That should last years....a tranny is thousands.
I've had the same rotors and pads over a year now, I still have 60% of the pads, and probably 80% of the rotors left, and I brake a lot, mostly city driving, and at high speed (55mph), so I don't worry about it. Also, its only the front brakes that will wear out, the rear ones last forever.
All in all I'd just go by what the manual says and not use it for engine braking....
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