GM past about 1978 is almost entirely metric too, depending on the engine combination and specific plant. I took an 1984 Cadillac apart a few weeks back and the entire drivetrain is Metric while most of the body stuff are SAE/inch. Very confusing amalgamation.
Tire treads are measured in 32nds of an inch, brake pads are measured in millimeters, brake rotor thickness is usually inches but sometimes millimeters, brake rotor diameters and offset are usually millimeters but sometimes inches, alignment measurements are usually degrees or minutes of angle sometimes also inches, pressures of coolant or tires are psi or bar...