- 1999–2001, 2003–2007 Factory-verified
2005–2007: heavy-duty models only (GM’s HD list)
M1F Factory-verified
Also described as Power take-off, rear
Also documented for Chevrolet
Documented applications
- 2001, 2003–2007 Factory-verified
- 2007–2008 Factory-verified
- 2000–2001 Factory-verified
the 2000 list words it as power take-off provisions
This page aggregates every documented appearance of M1F in the GMC reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.