The 1994 Chevrolet Chevy Van tire size depends on trim: the G10, 4.3 Z takes P215/75R15 100S; the G10, 5.0 H takes P215/75R15 100S; the G20, 4.3 Z takes P225/75R15 102S; the G20, 5.0 H takes P225/75R15 102S; the G20, 5.7 K takes P225/75R15 102S; the G20, 6.5 P takes P235/75R15 105S; the G30, Van Cargo Extended, 5.7 K, L05 takes LT225/75R16 D; the G30, Van Cargo Extended, 6.5 P takes LT225/75R16 E; the G30, Van Cargo Extended, 7.4 N takes LT225/75R16 D; the G30, Van Cargo, 4.3 Z, 4L60E/M30 takes LT225/75R16 D; the G30, Van Cargo, 4.3 Z, 4L80E/MT1 takes LT225/75R16 D; the G30, Van Cargo, 5.7 K, L05, 4L60E/M30 takes LT225/75R16 D; the G30, Van Cargo, 5.7 K, L05, 4L80E/MT1 takes LT225/75R16 D; the G30, Van Cargo, 7.4 N takes LT225/75R16 D, per the factory service manual.
Factory-Spec Tire Size
Varies by trim
G10, 4.3 Z: P215/75R15 100S
G10, 5.0 H: P215/75R15 100S
G20, 4.3 Z: P225/75R15 102S
G20, 5.0 H: P225/75R15 102S
G20, 5.7 K: P225/75R15 102S
G20, 6.5 P: P235/75R15 105S
G30, Van Cargo Extended, 5.7 K, L05: LT225/75R16 D
G30, Van Cargo Extended, 6.5 P: LT225/75R16 E
G30, Van Cargo Extended, 7.4 N: LT225/75R16 D
G30, Van Cargo, 4.3 Z, 4L60E/M30: LT225/75R16 D
G30, Van Cargo, 4.3 Z, 4L80E/MT1: LT225/75R16 D
G30, Van Cargo, 5.7 K, L05, 4L60E/M30: LT225/75R16 D
G30, Van Cargo, 5.7 K, L05, 4L80E/MT1: LT225/75R16 D