Hmm, had the dealer replace the two-piece rotors with singles, which is great. Except, I think my parking brake now has too much slack in it - when engaging, it clunks as the cable shield tensions up and hits the hydraulic lines for the diff. I think I need to take some slack out with the adjusters - does anyone know how to do that on the C7?

Seems like the C5 and C6 have star wheel adjusters you can reach from under the car, but I haven't found any info on the C7.

 

https://www.corvetteforum.com/forums...chematics.html

 

Thanks, actually read that first, and noticed the links to "parking brake adjustment". But we don't have that section...

On the bright side, I see the adjuster and I bet turning it the correct direction will move the shoes out. I guess I'll need to look and see if you can do that with the rotors on, that would be nice.

 

The adjustment is made before you reinstall the drum over the shoes.....no access to the star-wheel adjuster with the drum/disc installed...brilliant GM....

Parking Brake Adjustment

Special Tools

CH-21177 - Drum to Brake Shoe Clearance Gauge

For equivalent regional tools, refer to Special Tools See: Tools and Equipment.

Warning:
Refer to Brake Dust Warning See: Service Precautions\Brake Dust Warning.


1.Disable the parking brake cable adjuster. Refer to Parking Brake Cable Adjuster Disabling See: Parking Brake Cable\Service and Repair\Procedures\Parking Brake Cable Adjuster Disabling.
2.Turn the ignition to the OFF position.
3.Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle See: Maintenance\Vehicle Lifting\Service and Repair.
4.Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation See: Maintenance\Wheels and Tires\Service and Repair\Removal and Replacement.
5.Remove the rear brake rotors. Refer to Rear Brake Rotor Replacement See: Disc Brake System\Brake Rotor/Disc\Service and Repair\Removal and Replacement\Rear Brake Rotor Replacement.


picture


6.Set the CH-21177 - Drum to Brake Shoe Clearance Gauge inside of the drum portion of the disc brake rotor at the widest point.
•Place the contacts on the tool to the widest point of the park brake drum (1).
•Tighten the set screw on the tool prior to removing the tool from the drum.


picture


7.Position the CH-21177 - Drum to Brake Shoe Clearance Gauge over the parking brake shoes (1) at the widest point.
8.Turn the adjuster on the actuator until the park brake shoes just contact the CH-21177 - Drum to Brake Shoe Clearance Gauge.
9.Repeat steps 6-8 for the opposite parking brake assembly.
10.Install the rear brake rotors. Refer to Rear Brake Rotor Replacement See: Disc Brake System\Brake Rotor/Disc\Service and Repair\Removal and Replacement\Rear Brake Rotor Replacement.
11.Install the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation See: Maintenance\Wheels and Tires\Service and Repair\Removal and Replacement.
12.Enable the parking brake cable adjuster. Refer to Parking Brake Cable Adjuster Enabling See: Parking Brake Cable\Service and Repair\Procedures\Parking Brake Cable Adjuster Enabling.
13.Apply the electronic parking brake.
14.Place the transmission in NEUTRAL.
15.Raise and support the vehicle so the tire and wheel assemblies are clear of the ground.

Note:
If the rear wheels rotate during the following test, repeat the adjustment procedure completely.


16.Attempt to rotate the rear tire and wheel assemblies.
•The wheels should not rotate forward.
•The wheels should not rotate rearward, or should exhibit significant rearward drag.
17.Release the electronic parking brake.
18.Verify the rear tire and wheel assemblies rotate freely and do not exhibit forward or rearward drag.
19.If the rear tire and wheel assemblies do not rotate freely and without forward or rearward drag, repeat the adjustment procedure completely.

 

For posterity - those two posts combined are all the info I needed, the procedure is pretty easy. Release the cable following the instructions in djnice's post, then follow ersatz928's. Caliper bolt torque is 89 ft-lbs, and you definitely need the rotors off to get to the adjusters.

Since I don't have huge calipers or the GM tool, I spun the adjuster until the rotor barely fit, then backed it off past where the rotor became loose. No more clunk, since the cable is now pretty far from everything when the parking brake is applied.