While automobiles built on these three platforms had different bodies, they shared the same unibody construction technology using a separable elastomer isolated front subframe assembly, a design which first appeared in GM vehicles on the 1st generation X platform in 1962 on the Chevy II.

Automobiles built on these three platforms (F, K, and X) also shared front and rear suspension systems, with tunings engineered to each application.

The front suspensions used unequal length A-arms, coil springs damped with tubular hydraulic shock absorbers, ball joints, elastomer bushings, and recirculating ball steering boxes differing in ratios that were specific to the application.

Rear disc brakes were standard equipment in 1977 - this design later ended up with some 1979-81 Pontiac Trans Ams with the WS6 option.

At the same time the rear disc brakes were made standard equipment the front brakes received a modified steering knuckle which used a 12-inch disc brake rotor (shared with the GM B platform station wagons and C/D platform except limousines and commercial chassis) - the wheel bolt pattern was changed from the GM 5 x 4.75 (used with Chevrolets and lower end BOP automobiles) to the 5 on 5 bolt pattern used with the rest of the Cadillac RWD lineup (also with higher end BOP automobiles and Chevrolet/GMC 1/2 ton light duty trucks, vans, and SUVs).