Read Jason Cammisa's comments on driving the 2008 Mercedes-Benz GL320 CDI
I recently had the pleasure of putting 600 miles on two different Mercedes-Benz GL320s - about 40 miles in a snowstorm in Ann Arbor, and then 560 miles on another when I arrived in San Francisco a few hours later.
The GL continues to surprise me by feeling so much smaller than it is. I fit dumptruck loads of stuff in back and never wanted for more space. With six passengers on board, even the rearmost passenger didn't complain about a lack of room. And yet, from behind the wheel, you continually forget you're driving a huge truck.
The other time you forget you're driving such a huge truck is when you get to the gas station. Despite my every effort to blow the driveline sky high, the GL320 CDI managed an astonishing 19.6 mpg during its stay with me. And most of that was city driving.
To put that in perspective, I'm currently driving an underpowered Kia Spectra5 with a 5-speed manual transmission, and am averaging 21.3 mpg. The GL is not only twice the Kia's size, it's faster, too. Man, I love diesels.
The GL isn't without niggles: I love the roast-your-rear seat heaters, but can't stand that they turn their temperature down gradually. I don't like that the Sirius satellite radio has its own button on the COMAND interface when all other audio functions are accessed with an "audio" button. I don't like that the side mirrors are way too small for such a large vehicle.
I also don't love the transmission - it feels unnecessary to have 7 closely spaced gears in a diesel-powered vehicle. Accelerating from a stop, the transmission is banging off redline shifts faster than an F1 car. The 3.0-liter V-6 makes 398 lb-ft of torque all the way down at 1600 rpm - and revving it doesn't produce much additional thrust. Sounds strange, but I'd rather have five long, widely-spaced gears and manual control, so I could take advantage of the mid-range grunt rather than have the transmission constantly shift.
Turbo lag is barely perceptible, and as long as it's under boost, the engine is very refined and quiet. Sure, the new, gasoline-powered muscle-truck GL550 will beat the GL320 to 60 mph, but I'd take the oil burner any day of the week. In regular driving, it's more than quick enough. And I bet if I behaved myself, I could have seen 25 mpg overall.
Hybrid, shmybrid. If every large SUV was this quick and got this kind of fuel economy, you wouldn't hear so much complaining about the price of fuel.