Does the 1986 GMC C25 Pickup 2WD need premium gas?
Fuel grade varies by trim — see the breakdown below.
| Trim (engine / transmission) | Fuel | MPG | Fuel/yr |
|---|---|---|---|
| 4.3L 6-cyl, Automatic 4-spd, RWD | REGULAR | 16 | $3,900 |
| 4.3L 6-cyl, 4-spd manual, RWD | REGULAR | 15 | $4,150 |
| 5.0L 8-cyl, Automatic 4-spd, RWD | REGULAR | 15 | $4,150 |
| 5.7L 8-cyl, Automatic 4-spd, RWD | REGULAR | 13 | $4,800 |
| 5.0L 8-cyl, 4-spd manual, RWD | REGULAR | 12 | $5,200 |
| 6.2L 8-cyl, Automatic 4-spd, RWD | DIESEL | 17 | $4,600 |
| 6.2L 8-cyl, 4-spd manual, RWD | DIESEL | 17 | $4,600 |
The EPA records the fuel each version was tested on. Whether premium is strictly required or just recommended is an owner's-manual detail the EPA dataset doesn't include — so we don't guess it.
7 trim(s) · EPA FuelEconomy.gov · retrieved 2026-06-14.