Replace Front Rotors on a ‘66

[John L.]

I need to replace the front rotors on my ‘66 as they are below the minimum thickness requirement. Who are the preferred vendors I should contact to obtain new rotors? thanks

[Mark F.]

John,

I got mine rebuilt at Bair's Corvette, but they also sell new ones if that's what you need...

check it out...

https://www.bairscorvette.com/c2rotors.html

[Joe L.]

I need to replace the front rotors on my ‘66 as they are below the minimum thickness requirement. Who are the preferred vendors I should contact to obtain new rotors? thanks

John------


Once-upon-a-time, when front rotors were available from GM, they were available only as an assembly with hub. Quite frankly, that is the best way to replace the rotors. However, the GM assembly, GM #3867311 was discontinued in December, 1971 and replaced by GM #3998278 which was discontinued in July, 1999. I know of no brake/hub assembly for your application that is currently available. So, you'll have to purchase rotors without hubs, remove your hubs from the existing rotors, and install. I think any major brand rotor will be fine. However, if it matters to you, you're going to find that virtually all rotors available today, regardless of brand, are going to be of off-shore manufacture.

[Richard M.]

John, Are your rotors riveted to the hubs? If so, they're original. You'd have to remove them and drill out the rivets.

I suggest Bair's rotor and hub assembly in Mark's link. I'd think they could take your hubs as a partial exchange, or possibly use your hubs with new USA rotors, riveted and lathe turned.

If you just change rotors, your hubs may have excessive runout which will cause problems.

You would have to get them turned on a lathe as an assembly at a local brake shop, re-rivet or bolt together or simply place chiseled witness marks for future reference if removed.

An alternative method would be to just get new rotors and using a dial indicator, check for runout and use thin shim stock between hub and rotor. Personally, I won't use this method, but others have done this successfully.

Rich

[Patrick H.]

If you just change rotors, your hubs may have excessive runout which will cause problems.

You would have to get them turned on a lathe as an assembly at a local brake shop, re-rivet or bolt together or simply place chiseled witness marks for future reference if removed.

Rich

This is what I would do if you decide to replace them yourself.

Bring the assembly without bearings installed to a local shop, and have them turned so they are true. You can hold the rotor in place using backwards lug nuts, or some have tapped the rivet holes and used a countersunk head Allen screw to retain the rotors.

You can't just install the rotors and go driving, else your braking system will have problems with runout and air pumping.

[Joe L.]

This is what I would do if you decide to replace them yourself.

Bring the assembly without bearings installed to a local shop, and have them turned so they are true. You can hold the rotor in place using backwards lug nuts, or some have tapped the rivet holes and used a countersunk head Allen screw to retain the rotors.

You can't just install the rotors and go driving, else your braking system will have problems with runout and air pumping.

Patrick-----

What you suggest will work providing that the rotor-hub assembly does not result in excessive runout on the rotor. In that case, the machining process on the rotors can result in their being below the thickness limit. At the very least, some of the rotor's "wearability" is consumed in the process. It would not be this way ifUNFINISHED SERVICE rotors were available. As far as I know, they are not. When the rotor/hub assembles were originally manufactured, UNFINISHED rotors were installed and riveted to the hubs and then the rotors were machined. In this manner, the finished rotor was true to the hub centerline and the rotor thickness was set at the new rotor dimension.

One thing that can be done now, though is this: assemble the new rotor and and existing hub as you described above. Measure the rotor runout. Then, correct the runout using the TAPERED SHIMS available from Raybestos. If the rotor can be brought into acceptable runout specs with a shim(s), you're done. If not, a final machining can be done but with the use of the shims to correct most of the runout, the machining will remove a lot less of the rotor thickness than if shim(s) were not used.

[Gary R.]

John,
You can buy rotors from vendors and ship them to you. You will be paying more for an imported rotor and shipping. I use NAPA premium rotors, I am setting up a set now in fact. Available virtually everywhere in the country.

I would deburr both the hub and new rotors. Bolt them on and check the runout. I never cut rotors, front or rear.

I have been tapping and bolting them on using flat heads in place of the rivets for decades. Dialing the runout under 003". I have literally done this 100's of times and never had a problem or comeback.

However, tapping and bolting them on is not necessary, most don't do it. But you should torque all 5 nuts on the rotor when checking the runout and once you get them dialed-in, loosen and recheck. If the runout doesn't change, you're done.