LeTech Takes Off-Roading to New Heights in This G-Class

Totally squared up for adventure.

We may all love our lifted-up 4x4s, built to conquer any off-road challenge, but the truth is they can be cumbersome to drive for extended periods on the road. And while some more luxurious versions of our favorite off-roaders are certainly more comfortable and refined, they often sacrifice some of their off-road capabilities. So, does the perfect middle ground exist, or is it our destiny to compromise? For the German company LeTech, finding a solution was essential. Their team set out to take the already luxurious Geländewagen’s latest G63 generation, with independent front suspension (IFS), and make it even more effective on every type of terrain. To put their creation to the test, we took it to the Nevada desert, where Bill Rader Motorsports (BRM), LeTech’s distributor in the U.S., built the very first IFS W463A (a.k.a: the latest G-class) in the USA.

LeTech also offers a complete roof rack, an air deflector, a spare wheel carrier, and tough protective skid plates..

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About LeTech

LeTech is responsible for designing and manufacturing the portal axle conversion systems used on the factory AMG G-Class 6×6 and the massive 4×4 ‘Square’, officially presented by Mercedes-Benz last summer. With BRM, LeTech recently introduced an aftermarket, retrofit version of the conversion system for the new G-Class. This was perfect timing for BRM since a customer from California required an updated version of the factory 4×4 on his new IFS W463A G-Wagon. At the time of his decision, there were no official projections that a factory vehicle would be available, and the owner needed the additional ground clearance to browse his avocado plantation ASAP.

Putting 37-inch tires on a G-Class is a bold move! The G63, which has 20-inch HRE wheels equipped with Falken Wildpeak A/T3W 12.5” tires, should receive a new set of smaller Hutchinson x BRM rims to tackle more challenging terrain than the sand dunes we tested on.

Portal Axle Conversion

Portal axles have powered military vehicles since the 1940s. Since then, have become popular on forestry and off-road competition vehicles, particularly on Unimogs. The conversion to portal axles lifts the drive shaft to the top end of the hub using a gear system, which raises the axle and significantly increases ground clearance. The biggest advantage of the LeTech system is that the standard G-Class’s on-road behavior remains unchanged. “The use of portal axles also allows the suspension geometry to remain unchanged,” explains Bill Rader. “This means there is no change in road handling, while the transmission ratio inside the portal axles is exactly what is needed to compensate for the 37-inch tires. So, all electronic systems work normally, including the speedometer, ABS, ESP, etc.”

The conversion to portal axles lifts the drive shaft to the top end of the hub using a gear system, which raises the axle and significantly increases ground clearance.

There is 18 inches of ground clearance at the bottom of the rear differential housing and an impressive 19 inches under the front skid plate.

Bill Rader Motorsports

If one still needs to figure it out, Bill knows his stuff. He has two decades working on transmissions for Porsches and custom race cars that compete — and win — in major events such as the 24 Hours of Daytona, Le Mans, and the American Le Mans Series. With Bill and his team of engineers and technicians’ expertise in gears, they were able to ensure that the portal axle conversion system was indestructible. Their location in Nevada, between the Las Vegas Strip and the vast desert landscapes, makes them well-suited to test their Geländewagen preparations on pavement and sandy terrain.

Bill and his team of engineers and technicians’ expertise in gears, they were able to ensure that the portal axle conversion system was indestructible.

We are a far cry from the original military version of the Geländewagen. Leather, carbon fiber, brushed metal, a 9-speed transmission, a luxury sound system, and a large screen are all present – not to mention the legendary trio of locking differentials.

G-Class Foundation

The portal axle system is composed of a machined aluminum block with a series of gears of varying diameters that reduce the number of rotations between the half-shafts and the constant velocity coupling joint or universal joint depending on the type of axles and hubs. This reduction allows for larger wheels or shorter gear ratios. The G still gets some trick suspension with custom-made KW adjustable shocks and springs. At the front, a complete LeTech subframe receives the upper and lower control arms and sway bar. In the rear, stock G63 control arms, KW springs, and shocks make up the rear axle’s suspension, while LeTech outer tie rod ends complete the setup.

This results in the G-Class being raised 9.5 inches, making it almost impervious to rocks, ruts, and mud. Furthermore, this configuration widens the track by 8 inches, providing increased stability when crossing obstacles.

Thanks to the lift, the ground clearance at the lowest point of the front suspension arms reach 13”, and an impressive 16” at the lowest point of the subframe.

Off-Road Upgrades

Bill opted for HRE TR188 wheels, draped in a beautiful bronze finish and equipped with Falken Wildpeak A/T3W tires in 37×12.5R20. However, the German 4×4 should have a second set of wheels to tackle more challenging terrain than the dunes of our test drive. There, we can fully enjoy the G’s considerable torque and power. It responds immediately: as soon as you press right pedal, regardless of imperfections, it simply pulls nonstop. These all-terrain tires have quite rigid sidewalls but are a good balance between comfort and driving pleasure and grip in the rough stuff. With Bill at the wheel, it crosses sand dunes and rock steps face-on, sideways, forwards, and even backward (yes, really).

It responds immediately: as soon as you press the right pedal, regardless of imperfections, it simply pulls nonstop.

Besides the portals, shocks, and springs, a complete LeTech subframe, upper and lower control arms, and sway bar complete the installation in the front.

Standard G63 control arms, KW springs, and shocks make up the rear axel’s suspension, while LeTech outer tie rod ends were also added, which are part of the Portal conversion.

The Future

With all the testing and approval completed, Bill anticipates he will soon add a winch, custom BRM rock slide retractable steps, a central tire inflation system (CTIS), and most likely, Hutchinson x BRM bead lock wheels to make the G63 even more capable. The Mercedes-Benz is also equipped with Vision X 4.7 CG2 LED Light Cannons on the wind deflector on the LeTech roof rack. LeTech skid plates also protect the front end, and LeTech underbody protection handles the transmission and fuel tanks. In the meantime, the owner is enjoying it for a variety of purposes, including trips to the beach, off-road day trips in SoCal, and use as a daily driver on a massive avocado farm in California.

To learn more about Bill Rader Motorsports or LeTech, visit them online at billradermotorsports.com.

After building an international reputation in the world of Grand Touring racing, Bill Rader started preparing a G-Class equipped with German LeTech portal axles before the official launch of the new G 4×4².

Did you know?

The Shah of Iran’s request for a high-performance off-road vehicle in 1979 gave birth to the iconic G-Class, which has since served the armed forces of many major military powers and even been customized for the Pope. Despite plans to discontinue the G-Class in favor of the hyper-luxurious GL series, the vehicle’s loyal fans rallied together. They placed enough orders to persuade Mercedes-Benz to keep producing the beloved icon.

UPGRADES

2021 Mercedes Benz G63

Suspension: LeTech subframe, upper and lower control arms, and sway bar on the front suspension; KW springs and shocks on front and rear suspension;

Wheels & Tires: HRE TR188 20×10.5”, Front and rear backspacing: ET40; Falken Wildpeak A/T3W 37×12.5R20

Exterior Accessories: Vision X / 4.7 CG2 LED Light Cannon on Wind deflector on the roof rack; LeTech roof rack

Other Modifications: LeTech Portal axle conversion; LeTech outer tie rod ends

Editor’s Note: A version of this story previously appeared in the May/June 2023 print issue of Tread Magazine.