Just took our Cx-5 in for an oil change and they are saying we need to get new front rotors and consider changing the brake fluid after 34K miles.. Does this seem right? We have never owned a Mazda before but have never had this issue so soon in owning a car. I will say that I do feel that the brakes are not sufficient enough for how sporty and quick the CX-5 is with the Turbo.
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A lot goes into that question. Are they warped or just scored? Is the dealer recommending replacement on just the front or all four? You should get more mileage out of rear as a rule of thumb since the fronts do more of the work. I assume he wants to replace the pads too since worn pads are typically how the rotors are scored bad enough to require resurfacing or replacment. If they're just scored has resurfacing been ruled out? Some shops won't even resurface even if that's feasible; they'll tell you the difference in price doesn't justify it. Depends. It's hard to tell from the picture, but if not warped then resurfacing might be adquate.
On the other hand, light scoring is normal. Road junk particles get on there and it happens. You'd be hard pressed to find rotors with a just a few 1000k on them without some light scoring.
You could warp rotors in 10 miles from heat buildup if you're riding the brakes down a long mountain descent. I've done that albeit not on new rotors--fine before the mountain, warped right after. Lesson learned - brake, release, brake, release going down mountains. If you drive frequently in mountains or hills, even if not that extreme, longevity can be reduced. If you drive aggressively, as your post seems to indicate, that would reduce longevity.
Depending on circumstances, 35k miles is not unexpected. I've gotten as little as 25k on sh*tty Accord OEM rotors and 63k miles front, 78k miles rear on OEM Sienna rotors most recently.
A lot comes down to how they feel. If you're not getting any brake pedal vibration or steering wheel vibration or front end shimmy when applying the brakes (any of which would show up most braking downhill), you're not getting any screeching sound when braking indicating the pads might be scoring, and the brake pedal feels firm, then you're probably OK. If something doesn't feel quite right, as you suggest, some work needs to be done. How they feel is the first cut in determining whether you should do something.
As for brake fluid, the 2020 manual does not specify an interval; all it says is "inspect" up through 60k miles then repeat inspections. Whether the screen maintenance reminder comes up with something else I dunno since I'm not far enough along.
Funny story. My last two Toyotas were the same--no specified brake fluid interval. I've taken them to the dealer at every other oil change. Up to 90k miles in my current Toyota they said not a peep about brake fluid. At 90k the service rep recommended a change. I checked my service log, saw it had never been done, and gave the go ahead. What's the recommended interval, I asked? 3 years/36,000 miles. LOL, sorta. Though I had not detected any particular brake issue, I must admit they felt a tad firmer after the service. The fact of the matter is I don't think I've ever changed brake fluid at 3/36 in any vehicle I've ever owned over many years, makes and models. Long story short, 3/36 is probably the most conservative interval. I'm sure you can stretch that if the fluid has good color and the brakes feel fine.