Transmission Talk (CVT for beginners)

If you’ve followed my two previous pieces on servicing a GTS gearbox, then you may remember a comment at the start that I’d never done it before and actually had no idea what I was doing. Hardly the stuff to inspire confidence in the writer but it was a genuine observation that, despite knowing how to use spanners, I had no idea how an auto went together. Having serviced the engine, I was still none the wiser as to how it worked, even though I could now take one apart and put it back together correctly, and with no spare bits! Time to investigate then. How complicated could it be? As it turns out, not very complicated at all.

Basic principles

In its most basic form, the system consists of two pairs of opposing cones, each set nose to nose, in the form of a pulley. One pulley is attached to the engine output, the other to the road wheel. The two pulleys are mounted so that the gap between can be