18.05.12
Acronym has become somewhat tarnished, with recent versions topping a whopping 2,000 kg on the scales.
Something had to be done to put the SL on a diet, either that or rename it. Which is precisely what Mercedes have done. The diet, not the naming convention.

Next month, Mercedes-Benz will present a completely redeveloped SL Roadster made for the first time almost entirely from aluminium. The full aluminium bodyshell of this newly developed vehicle weighs around 110 kg less than a comparable steel bodyshell and is claimed to reduce the SL’s overall weight by 140 kg compared to its predecessor.
The designers use an even lighter material, magnesium, for the rear panel whilst high-strength steel tubing is integrated into the A-pillars.
“The effect is rather as if a heavyweight-class passenger had got out of the car and taken his heavy flight luggage, too” says Dr Thomas Rudlaff, responsible for the aluminium bodyshell at Mercedes-Benz.
Source: SkiddMark (press release)