Add to Cart Quaife Vauxhall F40 Gearbox Quaife Atb Helical Lsd Differential, Qdf21B $914.19 Quaife ATB Helical LSD differential for the GM F40 gearbox. A direct replacement for the standard open differential, the Quaife ATB Helical LSD differential transforms your car’s performance. Unlike a conventional plate-style limited slip differential,... $914.19 Add to Cart