Front brake disc replacement

Why does Haynes manual recommend replacing both front and rear disc brake pads when you do a brake job? On my 94 Camry XLE the fronts were down to the last 15 - 20 percent of pad while rears had over 50 percent bad thickness remaining. I purchased this Camry used, I don't know the history as far as brake pad replacement, but I saw no reason to replace the rear pads. So I didn't.

BTW I purchase OEM pads.

They may be thinking of the case where someone wants to use non-OEM pads or someone who has bought an older car and it is unknown what pads the previous owner kept on the car. If you know there are only OEM pads on the car, then I don't see why you can't just replace the worn pads. Since you don't know the identity of the brake pads in the rear, you better replace them all with the same composition linings. Having to brake at 60 mph in the rain is no time to find out your rear brakes lock up real easy compared with your fronts.

Different pad compositions will have different stopping capabilities (coefficients of friction) and/or have different rates of friction loss as they are heated. So, if you need to replace your front brakes and you don't know what you have on the back, replace them all so that you keep your front-to-rear braking balance, both cold and hot.

In addition to Brian's statement; take into consideration that in addition to the composite structure of the pad, also be aware that the front pads are under abuse more than the rear in regular driving situations.

My 89 V6 has rear discs as well. Since observing that the front pads wear much faster than the rear, I've only needed to change my rear pads every other interval as opposed to my front pads. This is as per daily driving in New York City. :grinyes:

Also, after you replace them, drive your car like your grandmother for a week or so to break in the pads. They will work much better if you break them in gently.