- 2026–2027 Factory-verified
requires CFF; 2026: not offered in 3SB, 3SC, 5SB; A/D in 4SC, 4SD, 5SC, 5SD; 2027: not offered in 3SB, 3SC; A/D in 4SC, 4SD, 5SC, 5SD
RYO Factory-verified
Also documented for CadillacChevrolet
Documented applications
This page aggregates every documented appearance of RYO in the GMC reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.