Premature Brake Wear

I just rotated the tires on my '05 Mazda 6 wagon yesterday and the mechanic (not at a dealership) told me that my rear brakes are 85% worn. Oddly, he says that the fronts are fine.



I thought this was pretty shocking as the car has only 23,500 miles on it. He is also telling me that my rotors have developed a lip and should be replaced.



Can anyone tell me if this is within the range of normal?



To be clear, I am not a particularly heavy-footed driver. I drive mostly in the city, and I make it a practice to coast.



Also, if it is relevant, I have had this car in a number of times because I am getting on the very low range of gas mileage - ~12-14 in the city.



Is it possible that there is a problem with my parking brake mechanism that is keeping the brakes engaged a little bit all the time?



Thanks for any help!





Thanks!

For mostly city driving this would not be considered abnormal wear. That may well also account for the low gas mileage.

While the rears wearing out first is unusual, it’s not unheard of. But because of that and the low mileage you may want to have them be sure the parking brake is adjusted properly and not dragging.