Does the 2020 GMC Savana need premium gas?

No. Regular.

$0extra a year

Miles a yearGas, $ a gallonPremium gap, $ a gallon

12,000 miles a year. Gas $3.20. Premium $0.60 more.

307 models (2020). One trim per model: the cheapest with a grade.

2020 GMC Savana: fuel grade by trim
Trim	Engine	Grade	Mpg	Regular, a year	Premium, a year
Commercial Cutaway 3500 Van 139" RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
Commercial Cutaway 3500 Van 159" RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
Commercial Cutaway 3500 Van 177" RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
Commercial Cutaway 4500 Van 159" RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
Commercial Cutaway 4500 Van 177" RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
Passenger RWD 2500 135" LS	4.3L 6cyl	Regular	N/A	N/A	N/A
Passenger RWD 2500 135" LT	4.3L 6cyl	Regular	N/A	N/A	N/A
Passenger RWD 3500 135" LS	4.3L 6cyl	Regular	N/A	N/A	N/A
Passenger RWD 3500 135" LT	4.3L 6cyl	Regular	N/A	N/A	N/A
Passenger RWD 3500 155" LS	4.3L 6cyl	Regular	N/A	N/A	N/A
Passenger RWD 3500 155" LT	4.3L 6cyl	Regular	N/A	N/A	N/A
2500 Cargo Extended RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
2500 Cargo Regular RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
2500 Passenger LS RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
2500 Passenger LT RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
3500 Cargo Extended RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
3500 Cargo Regular RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
3500 Passenger LS Extended RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
3500 Passenger LS RWD	4.3L 6cyl	Regular	N/A	N/A	N/A
3500 Passenger LT Extended RWD	6.0L 8cyl	Regular	N/A	N/A	N/A
3500 Passenger LT RWD	6.0L 8cyl	Regular	N/A	N/A	N/A

What this cannot tell you

Check the fuel door or manual before you fill.

Gas prices and the premium gap change by state.