2005 Chrysler Town and Country 3.8L. 225,000 miles. I am in need of some more education. Shaking during braking led me to warped front rotors. The left front indicated .009" run out. I replaced pads and rotors and all is well. I don’t remember when I did these brakes last, but the pads that I replaced were in brand new condition. Less then 1/16th" were wore off. I really don’t remember when I changed these last, but it must have been recently. My question is: why would these rotors warp with no wear on the pads. When I do brakes I am meticulous on cleaning and lubricating all surfaces. this is my family car so I used premium parts. If I was asked about this I would chalk it up as Drivers poor braking habits, but my wife doesn’t brake abusively. What can cause this heat? The only other two things I can think of is 1) I may have forgotten to seat the brakes the last time I did them or 2) I just by chance got a bad rotor, Am I missing something? And also I decided to change the pads even though they are new looking because of the uncertainty of the cause.
I am on my 4th Chrysler min van, the earlier ones, including yours, had undersized brakes and tended to warp easily - IMHO. On one of my vans I always replaced the front rotors and pads before going in for PA inspection because I knew they would not pass. PA is picky about scored and warped rotors.
A sticky caliper or corroded slide pins can prevent the pads from fully releasing
Where have you been?
Tester
Lug nut torque or crappy rotors my first thoughts. Ours had rust pits after 12k miles, Sticking caliper comes to mind, so many possibilities. Sounds like you know what you are doing, good luck to you.
Some rotors will warp because thier manufacturers did final machining too soon after casting the rotor. Cast iron tends to move a bit over the 2 to 3 weeks after casting. If it is machined too soon, it warps in use. No way to identify that before installation.
Also, tightening the wheel in a circular pattern instead of a star pattern can cause warping as well.
+1
Yup, that too…
And, I have to wonder if the OP’s wife is one of those people who ride the brake on long downgrades, rather than downshifting to a lower gear. On long downgrades, she might really overheat those rotors if she fails to downshift.
If these are now pads, you might be getting some resin transfer from the pads to the rotors and this can cause the shaking or pulsing. Your wife may be TOO easy on the brakes and not getting them hot enough to burn off the resin. A couple of moderately hard stops would burn the resin off.
If that doesn’t work, it could be any of the above, or it could be that there was some rust on the hub that wasn’t cleaned off when the new rotors were installed. This would throw the rotors “off plane” and look and act like they are warped when they are not. But that still involves removing the rotors to clean the hub mating surface.
Read more about this known problem with Chrysler minivan brakes here.
Tester
A 2005 with 225K, I’d say he missed that window. Good info though.
Thanks guys. I think so far I’m going for @Barkydog and @Mustangman with bad rotor or @Tester underdesigned brakes. When I discovered the run out I paid special attention to look for faulty parts and installation errors. I found none. Everything was clean. @Tester I did the rear brakes also. The pads were just a little thinner than the backing plate, so it was time anyways. I don’t think there’s a problem back there. I’ve had the car for 9 years and I don’t remember changing them, but I know I did them last because they had my trademark signature. So I am resonably sure it was once, a long time ago. Thanks everyone, let me know if you come up with something else.
For what it is worth, here is what I discovered with my '98 Civic:
-Don’t spend extra for nicer brake pads. When I did, my rotors tended to warp almost immediately, but they never warped with cheap brake pads. I mistakenly thought expensive pads would lessen warping. I was wrong. It was the opposite.
-Looking at a picture of the 2005 Chrysler Town and Country, it looks like it has plastic wheel covers. If it does, take them off and leave them off. The brakes will get more ventilation without them. Since I removed mine, my rotors only warped once in the last 15 years (right after I had expensive brake pads installed).
-For some reason, my rotors seem to warp most right after they’re replaced, which every shop insists on doing if I hire them to do a brake job. When I do my own brake jobs, I don’t replace or machine the rotors, I just replace the pads.
Replacing just the pads is pretty easy to do, but when you do it, you need to make sure you break-in the pads (a.k.a. “bedding” or “seating” the brake pads) so they fit against the ridges on the rotors, which the pads don’t do when they’re new and flat. It can be scary stopping those first few times if you forget to do this. All you have to do is speed up and slow down the car several times in succession, maybe driving around the block a few times. Don’t brake too hard, but don’t brake gently either. You want to wear the brake pads down just enough that they fit the contours of the rotor, but you don’t want to overheat them and warp the rotors.
I do remember in trade school the brakes class discussed that it was important to use compatible rotors if you use ceramic pads because ceramic has different friction properties. But out in the real world, I’ve never seen rotors specified for ceramic pads and mechanics I know, just use standard rotors on everything. So maybe under certain conditions it is worth looking into this. I have enough miles on this thing I shouldn’t have to do this again. If I do I’m definately going to go a different route. Maybe non ceramic. Thanks.
Another idea, rotors can fail a run-out test & seem to be warped, when the problem is actually the surface the rotor mounts too is uneven or the hub ass’y is bent. The way to prove/disprove is to measure the run-out with the rotor removed, assuming such a thing is possible with your configuration. Sketchy wheel bearings can cause this too.
In any event it’s always a good idea whenever the wheel is removed to make sure it is installed by torqueing the lug nuts in 3 rounds. If the final lug nut torque is spec’d at 90 foot-pounds, first torque them all in a star pattern to 30, next to 60, then finally to 90. Car on jack stands, wheel off ground when doing the first round. I do this in my driveway whenever a wheel is removed, even if the removal is done prior at a tire shop.