Until 1975, only 2WD trucks came equipped with disc brakes. The brake system used was the Chrysler Sliding Caliper type. The D100 had a 11.75 in. rotor and the D200 and 300 had a 12.82 in. rotor.
On 1975-88 models, the D100/150, W100/150, Ramcharger and Trail Duster series used the Chrysler Sliding Caliper with 11.75 in. rotor; the D200/250, D300/350 and W200/250 w/Dana 44 axle used the Chrysler Sliding Caliper with 12.82 in. rotor; the W200/250 and W300/350 with the Dana 60 axle used a Bendix Sliding Caliper with 12.88 in. rotor.