Master Cylinder Rebuild - DIY (1 Viewer)

[BigBen97]

Thats the first I’ve read of the warped rotor symptom which worries me. Was this only felt while coming to a stop and not necessarily applying brakes at highway speeds? While I come to a stop my rig will lurch forward and back kind of mildly, but enough to notice.

It was most times applying the brake.

Edit: for clarity, the pulsing went away with the master cylinder replacement. So what I thought might be warped rotors was resolved with this fix.

 

[2001LC]

Pulse during braking, is rotor disk run-out exceeding design limits. Which is commonly referred to as "warped" rotor. Easy to fix!

With "warped" rotors. The hotter the brakes disk of rotor and pads, the more pronounced the brake pedal or whole vehicle pulse feel.

Here's a video of "warp front rotors's disk" pulsing steering wheel. Driver was using brakes, to control down hill speed, which overheats brakes. A bad practice, we don't do in the Rockies. He had brake disk machine, with an OTV brake lathe (on the vehicle brake lathe). Problem solved! Cost start at $90 each rotor.

Some say just buy new rotors. You can. But labor to have them replaced, especial front is. Is very time consume and technical, most shop mess up. Turn (machining) OTV, has added benefit of truing to the wheel hubs.



I once had a freaky ABS master unit. Dang thing locked one rear brake. It's ABS valve to one side rear, activated during normal braking and would not release. So I'd not say some freaky ABS unit, couldn't keep activating for no reason. But not likely. Nor have I ever heard of it happening.

 

[JLink]

Thanks for the info in this thread. I got the dash lights and buzzer, hit the pump and it turned on, lights and buzzer turned off. A few days later the same thing happened again, so I spent the $1500 for a whole master cylinder assembly and changed it out. It was very easy and I didn’t remove any of the interior to do it. Just used an extension to reach the nuts behind the brake pedal. Hardest part of the project was bleeding the brakes. Had to borrow a tool to cycle the abs modules. In the end I saved $1,000 compared to what the local dealership wanted for the part, and who know what they’d charge for install.

 

[TexLexican]

What tool is out there to kick the ABS on?

Thanks for the info in this thread. I got the dash lights and buzzer, hit the pump and it turned on, lights and buzzer turned off. A few days later the same thing happened again, so I spent the $1500 for a whole master cylinder assembly and changed it out. It was very easy and I didn’t remove any of the interior to do it. Just used an extension to reach the nuts behind the brake pedal. Hardest part of the project was bleeding the brakes. Had to borrow a tool to cycle the abs modules. In the end I saved $1,000 compared to what the local dealership wanted for the part, and who know what they’d charge for install.

 

[uHu]

What tool is out there to kick the ABS on?

The tool would be TechStream, Toyota Tester, or similar. Easier way is to, after normal bleeding, do some braking on a gravel surface, which would make the ABS kick in and let out any trapped air or moisture. Then bleed again.