GM develops 8-speed auto

General Motors is working on developing a new eight-speed automatic gearbox, according to US journal American Auto Press.

Although GM hasn't confirmed as much, the journal's report suggests the transmission's existence is all but confirmed by the fact that the world's No 1 carmaker has recently filed a trademark for the name '8 Speed'.

The company has also reportedly submitted a trademark logo for the name, which, on first glance seems to say 'SPEED', but closer scrutiny is said to reveal that the S has a shadow outline of an '8'.

The eight-speeder could provide struggling GM with a much-needed fillip. The car-making juggernaut has started offering six-speed autos in a range of models -- including our own V8-powered Holden VE Commodore -- but Mercedes and Lexus have moved the game on by equipping certain vehicles in their line-ups with seven- and eight-speed autos respectively.

What's the benefit of providing more gears? Quite simply, it provides a greater spread of ratios, which makes it possible to have the engine spinning at the optimum revs for the situation. Theoretically, this adds up to improved fuel consumption and sharper performance.

Mercedes-Benz claimed as much when it launched the 7G-Tronic a few years ago. The Benz boffins boasted the seven-speeder could trim 0.3 seconds off the 0-100km/h dash (depending on the engine and vehicle), as well as significantly reducing thirst.

American Auto Press also argues (correctly, in our view) that shorter increments between ratios should help smoothen out each shift, making gearchanges almost imperceptible.

In all likelihood, GM's 8 Speed transmission will debut in future Cadillacs, before trickling down to brands/models lower in the hierarchy. The company used precisely this strategy with the 6L80 six-speed auto, which bowed in range-topping Caddies, but, as mentioned earlier, now also resides in V8 Commodores.

American Auto Press suggests that launching an eight-speed automatic would help to re-establish the sales of GM gearboxes. GM -- like ZF, BorgWarner and Aisin -- supplies a number of carmakers with automatic transmissions.

Will we see the eight-speeder in future Holden Commodore/Statesman models? Too early to say yet, but market forces could well make this a reality in years to come.