Mar.15 (GMM) Specialist publications are reporting a secret of the apparent speed of Mercedes' new W04 car -- a system known in the German squad's garage as 'Fric'.

Lewis Hamilton, Mercedes AMG F1 W04 practice pit stop Photo by: XPB Images

German television RTL is saying it probably stands for 'front and rear interactive control', or in other words a type of legal active suspension.

Electronically-active suspension is not allowed, but an hydraulically-controlled layout could be a key to Mercedes' unmatched pace in the twisty middle sector at the final Barcelona test recently.

Auto Motor und Sport said the Brackley based team has been "tinkering with the system for three years".

The report said Sauber is also now working on a version.