hey guys, anyone else have a case of this? im not extrememly hard on my brakes or anything but some how i keep getting warped rotors. anyone else have the problem? i machined my o.e. rotors a few times in the last year or 2 and so this time i just bought a new set. well about a month or so down the road its shuttering again. any ideas why it keeps doing this?

 

suprajztwenty
this is a guess but,calipers may not be letting loose all the way.Does it pull one way or the other when you are driving?Also do you get any road rumble when you are driving(I mean like wheel bearing sound)inner wheel bearings can go out,then brakes can rub and heat the rotors.

 

I was using cheap rotors and even cheaper brake pads, the $10 dollar lifetime warranty jobs. They eat the rotors alive. They are impregnated with too much metal that take the rotor with it when the pad wears down. This time I went with cheap after market rotors, but I went back with OEM pads-$50 a set. So far, after 3000 miles I'm still good. Two other things can warp rotors as I understand it---overtightening the lugs and hitting a puddle of water after hard braking. I now torque the lugs to 85 foot-lbs. I also bled all four wheel cylinders thouroghly and it seemed to help the brake pedal firm up some.

 

Some of the others have said this, so although I'm being redundant.....
Stay away from the cheap rotors. A lot of these are Chinese made and
aren't worth the cheap price you paid for them. Stay away from the 'lifetime warranty' cheap pads that a lot of chain stores sell. Not only do they chew up the rotors, they STINK under hard usage. (literally!!)
If your Aerostar takes the directional rotors, make sure they are on the correct side. Don't put your right on the left or the left on the right. Torque the lug nuts to spec. Don't use an impact wrench like I still see a lot of shops using. Make sure the mating surface between the rotor and the wheel is clean. A small piece of dirt or rust between the wheel and the rotor can warp the rotor when the lug nuts are tightened.
The avoidance of puddles is good advice, just hard to follow.

 

One other thing to be aware of is that the later models came with directional rotors. Their ventilation fins are curved to better expel air when turned in the proper direction. The proper direction is when the curved fins point backaward at the top of the rotor. It might be tempting to install them the other way, so that they scoop air inward when turning forward, but the way the vents work is by centrifugal force throwing the air outward. If they're installed thw wrong way, the air motion will be stalled, which will cause the rotors to overheat faster.

 

Guys,

I love this thread, 'cause we've all been here... I agree with all the mitigation strategies, but I can also state that the rotors will sometimes warp in spite of following best practices. I strongly feel that the rotors are too small for the vehicle, especially with what some of us ask of them. Do everything you can to help, but don't be surprised if it doesn't.

DadVan

 

I must agree with Dadvan; I griped about this before, but the brakes on the Aerostar are way too small. The way the caliper is part of the spindle, there is no easy way to replace it with something bigger from either another car or the aftermarket.

 

Ditto on the torquing. I used to think that my wrench hand was calibrated pretty well, but at least once a year I wound up having warped rotors -- not badly worn, just warped.

BUT, after I started torquing my wheels the problem went away.

Great thread. Real practical stuff from real people. The books don't cover that.