Replacing Rear Brake Rotors

[shaggydog]

I recently had to replace the rear brakes on my GX470 at 90,000 miles.

The dealer wanted big $$$$ so I decided to do it myself. so I replaced the pads and the rotors.

Taking off the Caliper, compressing the piston and removing the pads was easy.

However taking off the Rotor to put on the new one took all the time.

I spent a lot of time trying to figure out how to REMOVE the old Rotor and searched this forum

and the internet but did not see anything on this topic so here is the TIP to make the job easier.

THIS post assumes you know how to remove the caliper and brake shoes, this post tells you how to get the Rotor off

so you can put on the new one.

The rear brakes have the emergency brake pads on the INSIDE of the Rotor.

Once you remove the caliper and the brake pads the Rotor is easily accessable.

However in my case the rotor would NOT COME OFF.

REMEMBER the old fashion REAR DRUM BRAKES where the shoes push out against the drum when you pressed on the brake pedal ???The GX470 emergency brake is the same setup but its on the INSIDE of the Rotor.

The little brake shoes push out against the inside of the rotor when you pull the emercengy brake.

On the Rotor where the lug nut posts come thru look for a HOLE about the size you can put a screwdriver in.

Its the only hole thru the rotor so it should be easy to find.

ROTATE the rotor so this hole is at the BOTTOM of the rotor.

Take a flash light and in the hole you should see a little cog type adjustment which you can adjust with a

flat blade screw driver. If you do not see it right away move the rotor left or right until you do.

Take a flat blade screw driver and move the adjustment up or down to MOVE the Brake shoes inside the rotor IN or OUT.

I forget which way moves in or out but you can tell as the Rotor will LOCK up and you cannot turn it when you are moving the brake shoes OUT, or it will turn freely when you are moving the shoes AWAY from the Rotor walls.

Keep adjusting it until the Rotor can be pulled off, then put on the new Rotor and adjust the shoes back out

until the Rotor will not turn then back them off a bit until the rotor turns freely.

Put the new pads and the caliper back on and you are done

If I had known this little procedure it would have saved me several hours of work.

You should be able to do both sides in an hour or so

[mann777]

You have done a good job, but you have forgotten to check the fluid pressure of the master brake master cylinder As sometimes there is lot of air build up on the brake SS lines. For this you need to depress the brake pedal around 25-30 times till the reaction force becomes light and stroke becomes longer, this will allow to bleed air out, this engages the booster while you depress the pedal. All this should be done while the ignition is off. Now switch the ignition to "ON" and wait till the pump motor has stopped. You will hear a whirring noise for a few seconds > Just depress the brake pedal once, you will see the pressure build up and the master cyclinder is perfect for the run....

[aljodoro]

Thats interesting. What you described, pumping the pedal, should that be done everytime you work on the brakes? Such as inserting new pads. For example- when you push back the pistons to make room for the new pads. Thanks, Al

[mann777]

Thats interesting. What you described, pumping the pedal, should that be done everytime you work on the brakes? Such as inserting new pads. For example- when you push back the pistons to make room for the new pads. Thanks, Al

Absolutely, this is to ensure that there are no air bubbles or any vacuum in the SS lines.

[nc211]

shaggydog: you didn't to happen to set the ebrake when you started this proceedure did you? Like in step one, when you were positioning your GX to where you'll work on it and lift it? I ask, because it's sort of intuitive to want to set the ebrake for safety before lifting a car up with a floor jack. If the ebrake was gripping your rotor that hard, then I could only assume (1) you accidently set it, (2) it must have been dragging the whole time prior to this repair, or (3) a good whack with a rubber mallet on the side of the rotor should bust it loose from it's grime encrusted grip to the hub. I've made the ebrake mistake twice, once with my LS that nearly drove me nuts before figuring out what I had done, and the other on my 4runner a few years later, which I caught early on.

[ezoHIo]

Wanted to say thank you for this post. I was yanking on that rotor and it would move, but wouldn't come off. All I had to do was release the parking brake!!!