Vehicle SpeedTime MultiplierDetection DC ModifierFuel Consumption
LowBase ÷ 2+01 per tile
MediumBase ÷ 4+21 per tile
HighBase ÷ 8+41 per tile

Examples (using Terrain Table base times):

Terrain (w/ Road)FootLow SpeedMedium SpeedHigh Speed
Plains2 hours1 hour30 min15 min
Hills (Road)2 hours1 hour30 min15 min
Hills (Off-Road)3 hours1.5 hours45 min22 min
Mountains (Road)3 hours1.5 hours45 min22 min
Mountains (Off-Road)5 hours2.5 hours1.25 hours38 min
Swamp (Off-Road)4 hours2 hours1 hour30 min