Rear disc brake rotor removal

RANMURPHY

MEMBER
2004 TOYOTA SIENNA
3.3L
V6
4WD
AUTOMATIC
235,000 MILES

My rear rotors were replaced at a shop last year; in learning to repair the van myself, I discovered that the driver's side rotor was misaligned when it was put back on, and currently the access port is partially blocked and I do not think I can access the starwheel through it.

The parking brake needs adjusted (it is weak), which is how I discovered this problem. Many other errors were made by that shop, which I have been able to fix, but I am unsure how to proceed to remove the rear rotor in this situation.

The wheel can rotate, a bit, and I have not yet tried to use the screws to "push" the rotor free, as those holes in the rotor are, of course, also misaligned, and the pressing bolts will only have a partial surface to push against. Help? Thanks!

Oh, I am a complete novice, but I learn fast, and in the last month have successfully repaired the air intake/filter, cleaned the mass airflow sensor, cleaned the throttle/throttle body, replaced the PCV valve, replaced the thermostat (lots of parts removed/replaced), bled the cooling system, replaced the front brake pads and rotors, cleaned/lubed the calipers, and bled the brake lines.

I follow instructions to a T, and am enjoying all this. Except the part where someone put Loctite on the lug nuts of three wheels, and something that turned into a rigid, sticky silicone inside the rear caliper pins instead of lubricant or anti-seize - pins could not move, so rear brake pads had actually rusted in place. So much cleaning.

1 Reply

CARADIODOC

MECHANIC
33,871 POSTS

I suspect you are putting blame where none is appropriate. There is no wrong way to put the rotors on, and I have never paid any attention to that. The pushing bolts you referred to will work just fine regardless how the rotor is installed on the hub. The only reason for installing it in a specific orientation is so the original screws can be reinstalled. Those serve two purposes. Their main function was to prevent the rotors from sliding off when the chassis was flipped over on the assembly line. That is not likely to happen now. Their second value is to prevent rust from forming in those threads. A lot of mechanics throw those original screws away. I always put them back on to avoid worrying do-it-yourself customers who rotate their own tires or do other repairs.

We have to rethink your story about the parking brake. The adjuster for that is accessed through the backing plate. It is never accessed through the rotor because you would have to reach through the hub too, and that means taking the wheel off. If you have the wheel off, it would be silly to try to do adjustments through a tiny hole. Just slide the rotor off.

Your parking brake is a variation of Chrysler's design with a drum brake inside the rotor. That makes for a very simple, straight-forward caliper design. There will be a rubber or hard plastic oval-shaped plug in the backing plate to remove for access. Regardless, that is an adjustment that is rarely needed once it has been set. Parking brake shoes do not wear out like regular disc brake pads do. About the only thing that can happen is the linings might rust off the shoe frames. That will require the frame to move much further than possible to hit the drum, and you will see that as you can apply the parking brake as far as it will go, and encounter no normal resistance. Of course it will not hold the vehicle from rolling away at that point either. You can also have a rusted/broken cable. That too will result in no resistance when the parking brake is applied.

If, upon inspection, you do find a pair of parking brake shoes are badly worn down, that is due to that rear cable sticking in the applied position. The fix for that is to replace the cable and the shoes. Never try to lubricate a sticking cable. Any mechanic who repairs trade-in cars will tell you his horror stories about trying to save a sluggish cable, and how that car came back on a tow truck. There is no long-lasting way to fix the cable other than to replace it.

If it will help, you might find more dandy information in this article:

https://www.2carpros.com/articles/parking-brake-shoe-replacement