When performing a brake job on a Chevrolet S10, the brake rotors are commonly overlooked. Brake rotors do wear out over time, just like brake pads, but at a slower rate. Because of the sensitivity of the braking system, Chevrolet gave the S10 a set of specifications regarding the rotors. The two main specifications on the S10's rotors are original thickness and minimal thickness. The thickness of the rotor is measured at the flat, disc portion and is measured in thousands of an inch.
The original thickness is the thickness of the rotor when brand-new. This specification is important to assure that the rotor you are installing is the proper size to start with. The Chevy S10's front rotors have an original thickness of 1.140 inches and the rear rotors, if the truck is equipped with rear disc brakes, have an original thickness of .787 inches.
The minimum thickness of a rotor is the thinnest the disc portion of the rotor can be. If a rotor falls below this measurement, it must be replaced or damage may occur to the braking system. The Chevrolet S10's front rotors have a minimum thickness of 1.130 inches and the rear rotors, if equipped, have a minimum thickness specification of .735 inches.
While these tolerances may seem insignificant, it is important to follow them closely. Using a rotor that is below the recommended specification forces the caliper to overextend in order to press the brake pads against the rotor. This can create a leak from the caliper's internal seal, cause the caliper to lock up or, worst of all, cause complete brake failure.
