footloose42

I'm looking to replace all 4 rotors on my 73, and I'm reading some mixed material on what all goes in to it. I know I will need to drill out the rivets, but once I do, is it as simple as sliding the old rotor off, and sliding the new one on? Or will I have to deal with anything else like removing the wheel bearings or hubs, or perhaps the parking brake in the back?

I found the how-to document that CorvetteMagazine has on replacing the rotors on the C3, but their guide also involves replacing the bearings, races and grease seals. Are those parts I will have to remove as well if I intend to only replace the rotors?

Thanks.

Peterbuilt

To remove the front rotors all you have to do is remove the calipers first.
The hub will stay in place after the rivets are removed.

For the rear, it's the same except that you may have to back off the parking brake shoes and after replacing the new rotor you have to readjust the parking brake.

However, you may now have a 'run-out' problem. On the front wheels, GM machined the hub and rotor after they were assembled.
On the rear, the spindle and hub were machined together, this eliminated the run-out problem.

What's run-out?
It's when the rotor does not turn exactly parallel and it causes air to get sucked into the calipers and the brakes don't work properly.

What makes you think that you need all 4 rotors?
You can put a micrometer on the rotors and see if they are still good. Unless you can see a definite problem you should consider keeping the originals.

About rotor run-out:

mikem350

Agree with Peter, check before swapping. Runout can be a real problem!

Easy Mike

I agree. Factory rotors seldom fail and usually do not need to be replaced. Have you miked your existing rotors?

footloose42

The car has 72k miles on it. While replacing the front brake calipers this weekend I decided to measure one of the front rotors with a vernier caliper. I quickly measured the front driver's side at 1.20 in, though that was only measured quickly at one location (I didn't take multiple measurements around the circumference and average them). I suppose 0.015" is small enough that a mis-measurement could account for the difference.

I found several threads on here stating the stock rotors should be replaced at 1.215". Hence why I'm thinking of replacing them. My rotors look like they have 1 2/5 MIN stamped on them, though I suppose it is more likely that's actually supposed to read 1 215 MIN If the threads I've found on here are correct. Would you suggest I take it to a brake shop and ask them to measure them with a micrometer?

augiedoggy

just for reference... I still have my original riveted rotors and my car has 106k on it now... they surprisingly are in great shape with a lot of meat on them.

Scottd

Just to add to what everyone else has said......make sure they are OUT of spec before you replace them. I assumed my fronts were well worn because they were originals. After dicking around for 4 days with Chinese rotors and beer can shims to get my .005 runout, I measured the old rotors only to find they were still well within spec.

If you decide to replace them, the only tip I have for you in regards to shimming is this: Make sure you have 5 lug nuts on the rotor, and that all 5 are good and snug when you take your measurement. I was getting all sorts of crazy readings because I was only finger tightening the nuts and was only using 3 of 5. Its a PITA, that's for sure.

footloose42

How did you measure them, Scottd? Any particular method? I agree I don't want to replace them if I don't have to.