Original: The gearbox provided three forward and reverse gears in either high or low range, with top speed ranging from 5 mph (8 km/h) in 1st gear, low range up to 36 mph (58 km/h).
Simplified: The gearbox provided three forward and reverse gears in either high or low range. It gave a top speed ranging from 5 mph (8 km/h) in 1st gear, low range up to 36 mph (58 km/h).