Hello Paul, is it possible and safe to down shift a car with a manual transmission while stepping on the clutch, during high speed driving, from gear five to gear two when you reach a hump, pothole or are sloping down a dangerous hill descent? Katalemwa.
Hello, Mr Katalemwa, there are driving situations that may create the need to down shift a manual transmission by skipping gears from gear five to two. When driving down a steep descent, up a steep hill, slowing down at a hump, traffic light or maneuvering round a corner and even over taking. Down shifting to a lower gear may be a useful way to slow down the car or power it up for better control or driveability. How you perform the down shift from gear five to gear two matters because you can end up hurting yourself when the car suddenly slows down with a violent jerk, you might damage your engine, manual gearbox or clutch system. One requires to be skillful and experienced with the use of brakes and clutch as well as the accelerator to control the car and engine speed or revolutions per minute. One of the rules of thumb is to drive or down shift to particular gears at specific speeds and rev bands. For instance shifting downwards from the fifth gear to the fourth gear between 80 - 50 kph, shifting down to third gear between 50 - 25 kph, shifting down to second gear between 25 - 5 kph. Its crucial to match engine revs to gear shifts. Basically the higher the gears, the lower the engine revs and vice versa. Down shifting from gear five to four will increase engine revs and slow the car. However skipping gears downwards to two will cause sudden wheel lock, increase revs beyond the redline (above 3,000 or 4,000 rpm) potentially causing severe damage to the clutch, gearbox and engine valves. If you have to down shift to two its better to shift down through the gears four and three to allow matching of engine speed to gears or use the clutch and brake to slow down the car to between 25 - 5 mph when you can safely engage gear two.