2002 4Runner, warped rotors again?

[rayjj]

My wifes 2002 4Runner, with about 37k, needs the brakes done for the 3rd time already, and the rotors were replaced once already because they were warped pretty bad, and now it seems as if they are warped again, since there is a lot of pulsing and vibration when the brakes are applied. Is this a common thing with these vehicles? She doesn't drive it hard at all, so thats not even a possible culprit. When they were done it was a local shop that did them, but I am thinking of replacing them with a Powerslot/Hawk combo this time around and doing it myself. I've done brakes many many times in the past, just never on this vehicle. Is it a pretty straightforward job? Nothing unique about it and no special tools needed?

Thanks for any advice,
Ray

[Brian R.]

You better find out what's wrong, and it's not the brakes. Putting another rotor and pads will only cost you money and you will be putting a new set on soon. The problem is somewhere else.

Possibly the wheels are poorly torqued and warping the rotors. Maybe the brakes are overheating from bad assembly or sticking wheel cylinders, or a bad master cylinder or proportioning valve or something.

How's your gas mileage? You should be getting 15-18 mpg. If it's much less than that, it is likely the brakes are binding because of one of the above reasons (or some other reason I haven't thought of).

(Maybe your wife rests her left foot on the brake pedal without thinking about it?).

The brakes in your truck should last a long time.

[rayjj]

Good points to look into. I think I can rule out bad assembly or sticking brakes, as the ride has always been smooth and quiet. My wife consistantly gets at least 19mpg or more, and she is a very careful (sometimes overly!) driver and does not speed at all. Possibly overtorqued wheels, but one would assume that from the factory they were torqued properly, as the first set went after around 20k, and none of the wheels had ever been removed since day 1. Guess I will check the torque on them this time around as the tires were replaced at the beginning of the summer. Funny how the brakes on my Grand Cherokee have outlasted her, and I certainly drive much much harder than she does!

[Brian R.]

Actually, smooth and quiet are possible with sticking brakes, particularly if the master cylinder is defective. The factory pads are quiet under most circumstances. Wait a minute and I'll have some references for you.

Even overtorquing is probably ok (at least in moderation). The real problem is widely varying torque on the different lug nuts.

Just keep it in mind that there is something wrong, in addition to the damaged brakes.

[Brian R.]

http://i16.photobucket.com/albums/b8...nerBrakes1.jpg
http://i16.photobucket.com/albums/b8...nerBrakes2.jpg
http://i16.photobucket.com/albums/b8...nerBrakes3.jpg
http://i16.photobucket.com/albums/b8...nerBrakes4.jpg
http://i16.photobucket.com/albums/b8...nerBrakes5.jpg
http://i16.photobucket.com/albums/b8...nerBrakes6.jpg
http://i16.photobucket.com/albums/b8...nerBrakes7.jpg
http://i16.photobucket.com/albums/b8...nerBrakes8.jpg
http://i16.photobucket.com/albums/b8...nerBrakes9.jpg

[rayjj]

Thanks for the pics, looks pretty straightforward. Hopefully I can figure out what else is going on to cause the premature failure.

[Brian R.]

Post if you end up needing master cylinder or other information.

[rayjj]

Will do and thx! Of course it will be something major since the warranty just expired!