- 2008–2009 Factory-verified
UD4 Factory-verified
Also documented for CadillacChevroletGMCHummerOldsmobilePontiacSaturn
Documented applications
- 2004–2007 Factory-verified
- 2005–2007 Factory-verified
This page aggregates every documented appearance of UD4 in the Buick reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.