Built To Beat: Mountain Machines’ 1990 M998 Humvee

“If John Wayne drove a truck, it would be a Humvee.” If that quote doesn’t get you interested in Steve Ortner, then I don’t know what will. He might not be wrong either. Steve is the owner of this 1990 M998 High Mobility Multipurpose Wheeled Vehicle (Humvee).

Steve also just happens to be the owner of Mountain Machine. His company fabricates anything from automotive components to custom CNC machining applications. He is a big fan of the Humvee.

“It’s an extremely unique truck. Everything from the portal hubs and the axles to how the drive train works is just cool. Also the brakes being in board and the ground clearance are amazing. Pushing the drive train into the passenger compartment is just such a cool and different idea. It just is really cool to me,” Steve said.

All of the wheels have been fitted with a Mountain Machine central tire inflation system.

“It really is the quintessential American truck. It’s the John Wayne of trucks. That’s what that truck is. If you were going to make an Expendables Part XII, or whatever number they’re on now; if Arnold Schwarzenegger and Randy Couture had to go rescue some hostages, they would take that truck right there. I just love these things,” Steve admitted.

Steve got his chance to buy his first Humvee about five years ago. He was a square body Chevy guy before that, but he always had the dream of building a Humvee with a Cummins motor in it. Then Steve saw one with compounds sticking through the hood. While this truck is not a Cummins, Steve did accomplish that dream with a previous build.

Steve and Mountain Machine have now entered the aftermarket parts fabrication market. The company was already fabricating automotive components for parts suppliers to the Big Three automakers and other companies, so the transition was seamless. While they have a solid focus on the Humvee market, the company plans to expand into other automotive parts in the future.

“We try to be a little more selective about the builds we do. We don’t take on projects with daily drivers or anything like that. If you can’t be without your truck for 5-7 months, then you’re probably in the wrong spot,” Steve said.

There are some out there that may hear Humvee and think of the now-defunct Hummer brand. The confusion is understandable as the styling of the Hummer H1 strongly adheres to the original styling of the Humvee. However, the Humvee is a military vehicle and the Hummer H1 is a civilian vehicle.

Another unique element of the Humvee is the placement of the windshield wipers and fluid.

The differences include high gloss paint, wood trim, sound insulation, upgraded upholstery, convenience packages, and more for the civilian model. If you have ever been in the armed forces since the introduction of the Humvee in the 1980s, you know the difference.

The advantages of these trucks include great ground clearance, big tires, macho styling, and a unique and extremely durable drivetrain. Steve and his crew at Mountain Machine set out to use all of those advantages and to take them to the next level.

“You can’t do things that are halfway. It’s gotta be awesome all the way through. Once you decide to do something you have to go all out. We want people to look at our work and know that they can trust us with their stuff and that we will deliver a high-quality product,” Steve said.

King four-inch bump stops were added to help soak up the big jumps at the dunes.

The crew started with a 1990 M998 HMMWV. Steve explained, “We started with a completely stock truck. It came with a non-turbo charged 6.2-liter with a three-speed transmission. We immediately swapped out the 160hp 6.2-liter for a 650hp LSX 454.” The bump in power is noticeable, to say the least.

The crew at Mountain Machine swapped out the stock engine for a 650hp LSX 454.

All of that horsepower is backed by a 4L80E overdrive transmission. The Mountain Machine staff then added PCS Paddle shifters to provide just that little bit of flair. Fuel flow is controlled by a Holley Terminator EFI system with a touchscreen display mounted in a custom bevel in the dash. “Everything modern had to fit,” Steve stated. “The first time we installed that bezel in the dash, it was black and I didn’t like it. So we painted it green and now I love it. All of those components have to blend in. You can have things like the touchscreen dash and Cadillac push-button start. But you have to take the time to do it right. The guys that serve in these vehicles don’t take the easy way out. Neither do we.”

Steve and the Mountain Machine crew also took the time to respect the heritage of the ride. As an example, they chose to retain the stock switch for the headlights. “The entire rig has been converted to 12-volt now. We could have done a push button or digital switch, or we could have done anything, really. But what could be cooler then the switch that is already there? I wanted to give it the modern badass-ness that it deserves, but in the right way,” he said.

Modern interior details have been added, such as a push-button start and LCD touchscreen.

A billet-backed converter and NP261 transfer case ensure that all of the power gets to the wheels. That particular transfer case choice also allows for the truck to have two-wheel-drive. This is an option that no Humvee ever came with. It’s just one example of why Mountain Machine is a pretty exceptional source for all things Humvee. “These trucks are a lot of fun when you add power and two-wheel-drive. Along with the suspension upgrades, it really does drive almost like a sports car. It’s comfortable and a real performer,” Steve said with a smile.

A custom roll cage was added to protect all four passengers.

From there the choice was made to install a Wilwood big brake set up all the way around. It’s not enough to put together a rig that can go fast it also has to be able to stop. Detailed foresight like that will ensure a safe build for both customers and the public when this monster comes roaring down the trail.

Steve upgraded the suspension all the way around using a Rod Hall extended travel kit. King four-inch bump stops make soaking up big hits easy. A custom roll cage to protect all four passengers was then fabricated with the same attention to detail that is present throughout the build.

The Humvee sports Maxxis Trepador 37-inch tires with Raceline beadlocks.

Inside the vehicle, occupants sit pretty in Corbeau suspension seats. They are also buckled in via five-point harnesses from RJS for the ultimate in safety. Raceline beadlocks ensure that super-low pressures can be run. In addition, all of the wheels were fitted with a Mountain Machine central tire inflation system (CTIS). The whole shebang is then wrapped in Maxxis Trepador 37-inch tires.

The custom interior has suspension seats and fire extinguishers for all passengers, just in case.

At this point, there is some more calibration that needs to be done to complete the build. Steve explained, “We want to get the ECU and Holley systems to talk better to allow for menu options to work the CTIS. Ed Larson, Carl Sparks, KC Jewel, and Doug “Diesel” Strimbel are my guys. They’re really the best and will get it done. Right now, though,I’m honestly excited to just get out and drive it. We just got the plates and registration, so I’m ready to go. I might just drive it to work tomorrow.”

Steve Ortner with the crew who helped him build the Humvee. Ed Larson, Carl Sparks, KC Jewel, and Doug “Diesel” Strimbel.

If you happen to be up at the Silver Lake Sand Dunes in Mears, Michigan this summer, you will probably see Steve and his family. This Humvee wasn’t built to sit. It was built to be driven hard and fulfill its destiny as a sand blaster.

In fact, Silver Lake is what inspired this build. While Steve loves the Humvee platform, he could have chosen to build it a number of different ways. “Silver Lake is like popping a big old pimple on my soul. I don’t know why it does this to me, but I just love it there. I’ve done mud bogging, drag racing, tough truck competitions, and truck drags. But nothing compares to Silver Lake. It’s just my spot,” he said with a huge smile.

Steve is looking forward to getting out to the dunes with his family as soon as possible.

While work has always been a huge priority for Steve, his family is still number one. Both his son and daughter work with him at Mountain Machine. He admitted, “I have the best life ever! My wife and I worked hard to get to where we are. I get up in the morning and my grandkids come to the house. I get to hang out with them every morning and then come to work doing this. Then I get to come home and see them for a little while before they have to go home. It’s a pretty good life.” We should all be so blessed.

About the author

Christie Materni

As a photographer, and self-proclaimed "magic maker" for over 12 years, Christie loves to create anything from amazing images to great chocolate chip cookies. Traveling the country with her camera, husband, and sometimes a dog, in search of fast cars and tough trucks is her favorite way to spend the day.
Read My Articles

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