How do you shift from high range to low range

You'll want to downshift when heading down a steep slope to reduce riding the brakes or when greater acceleration is needed. Downshifting is much like upshifting: off the gas, press the clutch and move to a lower gear and get back on the gas as you let out the clutch. Getting back on the gas quickly is important since downshifting and not touching the gas will slow the car down as the engine compression fights the turning of the wheels ,which is what you want while going down a hill but not when you need to pass somebody. If you are already revving high in your current gear, downshifting may spin the motor beyond its rev limit, and you might throw belts or worse, throw a rod or valve which means it would be time for a major overhaul or engine replacement.