Bottom line: A 48A J1772 charger is the practical choice for the GMC Hummer EV and Sierra EV. Their large batteries reward faster charging, and the Sierra EV's optional 19.2 kW onboard charger can use an 80A circuit if you want maximum home speed.
Charging at a glance#
| Connector | J1772 (CCS for DC fast charging) |
| Onboard AC charger | 11.5 kW (Sierra EV up to 19.2 kW optional) |
| Recommended charger output | 48A (80A only with the 19.2 kW option) |
| Typical circuit | 60A (100A for 19.2 kW) |
What to know for the Hummer EV and Sierra EV#
The Hummer EV and Sierra EV have some of the largest battery packs available, so a full recharge takes longer than for a typical EV. A 48A Level 2 charger delivers the fastest home speed the standard 11.5 kW onboard charger can accept, which makes it the right default for these trucks.
The Sierra EV offers an optional 19.2 kW onboard charger on some trims. Using that full rate requires an 80A-capable charger on a 100A circuit, which is a meaningful electrical upgrade. For most owners, a 48A charger plus DC fast charging on longer trips is the more sensible setup.
Recommended chargers#
How to choose#
- Plan for a 48A charger and a 60A circuit as the baseline for these large-battery trucks.
- Only pursue an 80A charger and 100A circuit if you have the Sierra EV's 19.2 kW option and need maximum home speed.
- Confirm the charger's cable can reach the truck's charge port given where these vehicles park.
Common questions#
Yes for overnight charging. The Hummer EV's onboard charger accepts up to 11.5 kW, which a 48A charger delivers. The large battery simply takes more hours to fill than a smaller EV would.
It can. The Sierra EV offers an optional 19.2 kW onboard charger on some trims, which needs an 80A charger and a 100A circuit to use fully.