2009 Mercedes-Benz CL550 4MATIC

Okay, admittedly the graceful coupe pictured here is not aimed at plutocratic off-roaders, but the engineers on hand at its launch proudly recalled an instance while mountain testing when they encountered a team of fellow development engineers shaking down a proper off-roader. Upon hiking the AIRMATIC suspenders up to tippy-toe mode, their graceful and gorgeous coupe managed to tackle a trail that impressed the truckers.

This feat of derring-do was made possible by the addition of the S-Class's spanking new 4Matic all-wheel-drive system, which splits torque 45/55 front/rear and incorporates a wet-clutch limited-slip center differential. As in the S-Class, the system's compact design allows it to package in the same transmission tunnel the rear-drive models use, and Mercedes claims that at 154 pounds, it's the lightest system of its kind.

Other changes to the car include substitution of the less expensive AIRMATIC suspension for Active Body Control (which is said to be incompatible with 4Matic). This helped trim the price sufficiently to make 4Matic standard on all CL550 models with no substantial price increase, and they're throwing in heated and cooled front seats and keyless-go for free (a $1960 value!). The rest of the CL lineup sticks with rear-drive.

Why add 4Matic to this uber-lux coupe? Today the 3700 or so CLs sold in this country are mostly distributed among the coastal and southern states, and all-wheel-drive is expected to boost the CL's appeal in the snow-belt.

The addition of 4Matic shouldn't dissuade any buyers. The lightweight system exacts no fuel-economy penalty (EPA ratings remain unchanged at 14/21 mpg city/highway), and 154 extra pounds go unnoticed in this 2.5-ton sled.

A brisk drive in the hills of eastern Austria further indicated that on dry pavement there's no evidence of the front wheels being driven. The steering wheel never tugs or twitches when powering out of a switchback-in fact, the stability control still intervenes just a bit in tight-radius, high-torque corner exits. You may feel pebbles striking the floorboards when powering up the pea-gravel drive to your Jackson Hole retreat, but that's a good thing.