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Rust-welded brake rotors

In tackling a warped disc brake rotor on a 16-year-old car, I knew I was in for a bad day when I first had to beat the wheel and tire off with a hammer. Thereupon ensued three days of Liquid Wrenching, propane heat, and at least 150 blows, from all angles, with various hammers, including a full sledge; no rotor-hub separation rewarded these efforts. I put it all back together and am driving again, with the oscillating brake. Does anyone have other tricks for breaking a rust bond (a weld, really) in a situation like this? I can’t imagine a puller would do the job if a sledgehammer couldn’t…

A 16 year old what?

What kind of car? Are you sure that the rotor isn’t part of the hub?

Most ‘top hat’ style rotors have threaded holes in the face of the hub that you can put bolts in, and use the bolts like pullers to separate the rotor from the hub. The trick is to find a matching bolt to the threads. Usually there are two holes, and you should use two bolts to pull on it evenly.

I have seen many rear drum nightmares, but front rotors? I sense operator error.

I think you’re right oldschool.

Your’s Doesn’t Have Rusted Over, Little Flush-Top, Counter-sunk Retaining Screws, Does It?

This happened to me on a 4 year old Camry. The puller broke out the extraction holes and I beat on it more than I normally would out of frustration but fear of damaging the bearings keep my anger in check. I ended up cutting the rotors off with a sawzall. It actually went very fast and did no further damage. They sprung open like a popcorn kernel when I got close to the hub and then practically fell off. There was a convenient notch in the knuckle where the saw blade could run free all the way down to the hub. I suspect it was there for a reason :wink:

I should add, on these hub centric designs, the rotor fits very tightly over the hub and the Camry also has a “hat” design. The inside of the “hat” rusted and expanded enough that it was permanently wedged in position. No amount of hammering would have removed it. Heat is a no-no around bearings so mechanical sawing seemed to be the best option.

This is a Mitsubishi Expo wagon. The front rotors are a “hat” design, and they do have threaded holes for pushing the rotor off the hub; the thread are rusted out. I think I’m headed down the sawzall route…

That being said, this car, driven in New England salt, is now encountering so many difficult repairs (brake lines, etc.) due to rust that I think it’s time may have come.

Since the “push off” holes are rusted out, and they may have 10 mm threads, you could tap them to 11 mm, or 7/16 inch. Use penetrating fluid on the hub-rotor interface.

The easiest way: Grinder/Hacksaw/Screwdriver/Hammer in that order. I have done this several times and it only takes about 30 minutes per rotor. I use a grinder to “slice” into the disc portion of the rotor, perpendicular to the rotor face, until I am fairly close to the hub. I then use a hacksaw to cut the rest of the way down to the hub assembly. After cutting through the rotor, place a flat-head screwdriver in the fresh cut and begin hitting it with a hammer until the rotor cracks and falls off.