CVT requires special attention

Chad Bryan, Gleaner Writer

Some motorists who drive a continuously variable transmission (CVT) vehicle may not even realise it until they need to change the oil, as there are significant differences with conventional transmission vehicles.

A CVT is a stepless automatic transmission which offers the motorist superior driving comfort and up to seven per cent lower fuel consumption and Co2 output. This unique mode of operation makes the transmission special.

It does not have a gearbox with a set number of gears, as with the conventional transmission, so this means the CVT does not have the transitional interlocking, toothed gears. The most common type of CVT is one which operates on the pulley system, which allows for infinite variability between the highest and lowest gears, with discrete steps or shifts.

NO GEAR-CHANGE FEELING

Andrew Jackson of used-car dealers Jetcon has considerable experience with the CVT transmissions, which are being shipped in second-hand cars from Japan and other countries with increasing regularity. "With a regular transmission you are changing gears - one, two, three, four, and you can feel that change in torque and change in pull. With the CVT, it is a continuous variation from the lowest to the highest gear and you do not feel the changes," Jackson said.

Since this transmission provides for more useable power, better fuel economy and a smoother driving experience than regular transmission, Jackson pointed out that CVT is far more efficient. Though he could not say definitively when the first vehicles with this transmission started entering the island, he pointed out that they had been present in the Subaru Justy of the late 1980s.

In maintaining the transmission, Jackson said CVT oil must be used. He added that there are different types of CVT's - one utilising a chain and the other a belt, which require the right amount of their own specialised oil. Regular transmission oil should not be used on a CVT as this could result in deterioration of the mechanism and could cause noise, Jackson added.

The CVT requires far fewer oil changes than regular transmissions.