I had to add brake fluid twice in about a month to maybe six weeks time, after some mountain driving. The light would come on; I'd add fluid and drive a couple weeks, then light pops on again. I crawled around underneath, but couldn't see a leak anywhere. I also felt in back of the master, but nothing.

So I took it to the local dealer (the one in Scottsdale is renowned for great, honest service) and they said it was due to the rear pads being so far down, and that the fluid was going into the rear pistons. They said they found no leaks including at the master cylinder. They said the pads were down to needing replacement, so I had them do it and turn down the rear rotors (first time).

So I'm wondering about two things:
1. Why would I have to add fluid twice in about a month? I've certainly experienced where pads wearing causes the pistons to use more fluid, but why would it be down twice in a few weeks, to the point that the light came on both times?

2. I had the rear pads changed at 198k and now have just under 235k, so why would the pads need changing again? I was in the mountains when I had them changed last time (198k) - do you think that mountain shop perhaps used really cheap pads . . . or didn't turn the rotors?

I had always had rears last 2-3 times what the fronts would before needing changed. But the service writer told me the the electronic proportional braking system may actually have the rears engage a couple nano-seconds before the fronts, to keep nose dive at a minimum. And supposedly, because I tow a trailer occasionally, the system might apply more power to the rears. But to have them needing replacement after only 37k doesn't make much sense to me . . .

I'm puzzled!

What do y-all make of this?