1975-82 - 3 Inch Wide Springs
C50 through C70 with 3" Wide Springs, including "High Cab" Kodiak/TopKick
1975-1982
S50 through S65 and B60 School Bus Chassis with 3" Wide Springs
1975-1982
P40/45 with 3" Wide Springs
1967-1982
For C and S-Series from serial no. 140000 (Chevrolet) and 590000 (GMC) (mid-year 1975):
True radius, rubber (RB-75) eye leaf bushing springs with high (approx. 8") arch.