Transmission, 9 speed automatic, 9T45, electronically controlled, overdrive

Years 2019 Models 1 Factory citations 1

Documented applications

Terrain — Second generation (D2XX) (2018–2024)

2019 Factory-verified

SL, SLE, SLT: S; only with the LYX engine

GM factory document — 2019 gmc terrain order guide copy gm authority, p.10, p.45.

This page aggregates every documented appearance of M3U in the GMC reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.