I Crawled Under The 2019 Mercedes G-Class With One Of Mercedes' Head Engineers
The new 2019 Mercedes-Benz G-Class may look the same on the outside, but there are some huge changes underneath. So I sat down—well, technically, crouched down—with G-Class head of development Oliver Metzger to look at some hardware. It was awesome.
For the past 40 years, the Mercedes G-Class has used a solid axle front suspension setup. But now, for the first time, it's getting a double-wishbone independent design, and—at least for diehard off-roaders—that's a big deal. So when I got to the Detroit Auto Show, I decided to have a close look under Stuttgart's beefiest off-roader.
I'm not sure exactly why, but G-Class's head of development, Oliver Metzger—who was wearing a nice sport coat—agreed to crawl on the dirty ground under his new SUV and show us some cool technical bits. Perhaps it's in his blood as an engineer to look at hardware—all I know is, he was a great sport.
The first thing we looked at was the new independent front suspension, which many off-roaders will consider a step backwards in terms of rock-crawling capability. But, as I've stated in my article on the new setup, IFS actually seems to make sense for a luxury vehicle like the G-Class, as it can offer improvements in fuel economy, steering and—importantly—handling.
Metzger more or less echoed those sentiments. "I think you're absolutely right," he told me. "If you go to an off-road vehicle, you should go and choose a rigid front axle." The goal for this new G-Class, however, was to make strides in on-road performance. "If you want to improve on-road performance," he told me while lying next to me behind the driver's side wheel, "you get very quick to the limit with a rigid front axle."
That said, if you look at the G-Class's press release, you'll see that Mercedes claims the new vehicle actually outperforms its predecessor in the rough stuff. Part of that has to do with the fact that, according to Mr. Metzger, the old solid axle was limited in terms of flex. "Due to some legal requirements, we had to lower the whole drivetrain a little bit," he told me. "And this would not even allow us into the rigid front axle to keep the wheel travel."
Thus, the 2019 G-Class's independent suspension actually offers more overall articulation. There are about 2.2 inches more up-travel, and about 0.2 inches more in rebound. "So in total we have almost [7.9 inches] of wheel travel," Metzger says.
The rear suspension stays a solid axle, though Metzger says it's now a five-link versus a three-link setup. In other words, in addition to a track bar and a trailing arm on both sides, there's also an upper arm on each side. Here's a closer look at the upper and lower control arms, which are set up similarly to the new JL Wrangler.
The five-link setup, Metzger says, is for better on-road and off-road handling. And apparently it doesn't hurt articulation. "We increased also here the wheel travel," Metzger said as he both laid on our sides staring at the rear stick-axle. "So we have about [9.8 inches] of wheel travel in the rear." The lack of a rear sway bar helps in that department, Metzger told me.
Ground clearance is also up, in part due to the fact that the independent suspension could be mounted high, directly to the frame. This yields 10.6-inches of clearance up front. And out back, the differential pumpkin sits about a quarter of an inch higher than the outgoing model's, yielding 9.5-inches of distance between it and the ground.
The raised position of the front control arms directly on the frame—and the large distance between them—required a strut brace in the engine bay to stiffen up the chassis for rugged off-road driving. There's a look at it in the photo above.
There are also adaptive dampers on every corner, plus the three things that Metzger says make the G-Class "the" off-roader: a rigid frame, three locking differentials and a two-speed transfer case. That transfer case, I noticed while crawling under the new G-Class, did not appear to be protected.
Nor did the new nine-speed automatic transmission's oil pan, which looked to be made of some sort of plastic:
Whether there are normally skid plates covering those two components, I'm not sure. This was a display vehicle that had some sort of wire going up through the body, presumably to power the interior bits. I've asked Mercedes if the trans and transfer-case get some armor on the production models; I'll report back when I learn more.
Metzger and I also had a look at the G-Class's air induction system, which includes a secondary intake located at the top of the radiator support. Normally air gets pulled into the engine through the grille, as that's where there's high pressure, meaning better volumetric efficiency. But air gets sucked in through the secondary intakes from behind the headlights when a sensor detects water.
"The wading sensor senses the water. And as soon as it senses water, we have a flap," Metzger mentioned as we looked underhood. "And it closes the flap and we have a secondary intake channel." Metzger explained in short how it works, saying "Immediately when you go into the water, the engine gets its air from up here. And it comes from behind the headlamps." The result is that the new G-Class can ford 27.6-inches of water compared to 23.7 on the outgoing model.
Other improvements worth mentioning include a one-degree higher approach angle (now to 31 degrees) and a one-degree higher breakover angle (now to 26 degrees) despite the longer wheelbase. Mercedes also mentions in its press release that the approach angle remains at 30 degrees, and that the new G-Wagen can climb 100-percent slopes (45 degrees). Both solid figures.
So overall, the G-Wagen definitely still seems legit—especially for people who plan to keep it stock. It still has lockers, it still has solid approach and departure angles, it's still got a low-range gearbox, it still has a ladder frame, and it still has one solid axle. I look forward to driving this thing to find out if the lack of another solid axle did much to compromise off-road capability. Based on what Mercedes' head of development for the G-Wagen tells me, the thing should still be a beast.