JEEP'S best ever performing model, the Grand Cherokee SRT8, is to cost £58,995 while rugged stablemate the 3.0 CRD Overland Summit is priced at £44,795.

The fiery new SRT8, which stands for Street and Racing Technology - the sports arm of the Chrysler Group - offers a blend of capability and performance plus advanced technologies.

SRT raises the game to the point where the V8 can accelerate from 0-60 mph in 4.8 seconds, on to a top speed of 160mph, yet can brake from 60-0mph in just 116 feet.

Beneath the bonnet is a whopping new 6,424cc HEMI V8 engine with Fuel Saver Technology that delivers 470bhp and 465 lb ft. of torque - an improvement of 50bhp and 45 lb ft. torque over the 6.1-litre HEMI V8 it replaces.

Fuel Saver Technology works by alternating between fuel-economy four-cylinder mode when less power is needed and a sporty V8 mode when more power is in demand.

The 2012 Grand Cherokee SRT8 also comes with 45 specific safety and security features including active head restraints, adaptive cruise control, forward collision warning and rain brake support - which periodically dries the brake discs in wet conditions.

The new Overland Summit model, meanwhile, offers extra luxury and refinement and comes in an exclusive Rugged Brown paint scheme with fully chromed grille and fog lamp bezels plus 20-inch aluminium wheels.

Powered by a 237bhp, 2,987cc V6 CRD diesel engine, the Overland Summit boasts real wood interior trim, saddle-coloured Nappa heated and ventilated leather seats and Berber floor mats.

Standard kit includes adaptive cruise control, forward collision warning, blind spot monitoring and rear cross-path detection systems.

Both new models are available to order now.