Short answer: The 2018 Silverado 1500 uses a 6-speed automatic transmission across its engine lineup; an 8-speed automatic was not offered in the 2018 model year, but Chevrolet introduced an 8-speed unit starting with the 2019 refresh. This article details how the transmission applied to the 2018 Silverado and how the lineup changed in the following year.
Overview of the 2018 Silverado 1500 transmission options
Before listing the specifics, it helps to know that GM’s Hydramatic 6-speed automatics were standard across the 2018 Silverado 1500 range. The 8-speed automatic was not available on 2018 models, and buyers looking for more gears would encounter the update in the 2019 model year. The following breakdown outlines the transmission setup by engine for 2018.
- 4.3L V6 engine: 6-speed automatic transmission (GM 6L80 family)
- 5.3L V8 engine: 6-speed automatic transmission (GM 6L80 family)
- 6.2L V8 engine: 6-speed automatic transmission (GM 6L80 family)
In short, all standard engines in the 2018 Silverado 1500 used a 6-speed automatic, with no 8-speed option offered that model year.
2019 update: the move to an 8-speed automatic
For the 2019 model year, Chevrolet upgraded the Silverado 1500 to an 8-speed automatic across the lineup, aligning with updates seen in other GM full-size pickups. The shift aimed to improve acceleration, overall performance, and efficiency compared with the earlier 6-speed setup.
What changed and why it mattered
The transition to an 8-speed automatic provided smoother gear transitions, better highway fuel economy, and improved towing dynamics for many buyers. For prospective used-car shoppers, this means a 2018 model will have a different feel and performance profile than the post-2018 models with the newer transmission.
Summary
As of the 2018 model year, the Silverado 1500 relied on a 6-speed automatic transmission across its available engines (4.3L V6, 5.3L V8, 6.2L V8). Chevrolet introduced an 8-speed automatic starting with the 2019 refresh, marking a notable upgrade in gearing and efficiency for later models.