In 2018, we got our first taste of Mil-Spec, a company that wanted to do with Hummer H1s what other resto mod companies like Singer and Icon have done with other classic cars. The initial range of sprung Hummers showed quite a bit of promise with a range of mechanical upgrades, including a particularly powerful and entertaining diesel engine, plus significant improvements to the interior’s livability and luxury. As good as the first trucks were, Mil-Spec wanted to do even better. It focused on details such as better materials and ergonomics for what it calls the second-generation restored H1s. And all those upgrades can be seen in the M1-R, which uses the second-gen M1 and adds some pretty extreme customer-requested tweaks.
What is that? Oh nothing, just a Mil-Spec M1-R rolling through ## autoblog ## hummer ## m1r ## custom ## fyp
♬ original sound – Autoblog
As with all Mil-Spec Hummers, the M1-R has undergone extensive restoration, with the body and frame reduced to bare metal. It was re-coated in a durable bedliner-like material made with pieces of Kevlar. This one was tinted to make it look like one of the factory colors H1, Competition Yellow. Steel off-road bumpers, a front brush guard, a tubular rear tire rack, fender flares and door panels finished in solid black add contrast and give it a more rugged look. The simple and robust 20-inch Black Rhino wheels look good on the truck too, especially packed into the 38-inch off-road attempts.
Most of the improvements in the second generation M1 can be found in the cab. As before, each upholstered surface is made of leather, in this case with diamond stitching that the customer requested. It’s all done in-house (fun fact, Mil-Spec now also does upholstery for private jets). Virtually every non-upholstered surface is made from machined aluminum. That includes the steering wheel, the climate control knobs, air vents, window switches, turn signal levers, even the custom ignition key. They all look and feel great with a hefty weight and sharp edges. The toggle switches are a special treat, returning a light, mechanical click with every press. Some of them are a bit difficult to get to due to the Hummer’s odd interior layout, but that would be the case even in a standard Hummer. These aluminum pieces are a huge step up from the plastic toggle switches and air vents used on previous Mil-Spec Hummers.
The interior is now also more functional and comfortable. The shift lever has been replaced by a series of push buttons and a new steering column has been added, giving the driver more hip and knee room. The gauges have been rearranged and the speedometer moved to the right side of the handlebars. This is because the speedometer was quite large and tended to be blocked by the wheel, so it is now more visible. The climate control now has more fan and temperature adjustments for the air conditioning, instead of the original model’s two choices: on or off.
While Mil-Spec has made major improvements to the interior, not much changes to the mechanical parts of the standard M1, which continues with a 6.6-liter LBZ Duramax diesel V8 that produces a healthy 500 horsepower and 1000 pound-feet. releases. couple. However, the customer who ordered this M1-R wanted something more than standard. This LBZ engine is built by HSP Diesel, with a bigger turbo, bigger injectors, improved cooling and more aggressive engine tuning to produce 800 horsepower and 1200 lb-ft of torque. It is combined with a similarly hefty six-speed automatic transmission. This M1-R also featured long travel Rod Hall Racing suspension and Wilwood six-piston brakes for all four wheels. And like regular M1s, it gets stronger than standard axles, ARB air-lock differentials and a Warn winch.
We got to drive the truck about a week after the assembly was complete, and as such the engine was still running in and spinning a tentative tune. As a result, it didn’t produce full power and coughed out quite a bit of soot, but Mil-Spec says all of these issues would be resolved before the truck is delivered to the customer. Plus, we didn’t have a particularly long drive as the customer was concerned about the media powering their new baby. Still, we had enough time with it under different driving conditions to get a good feel for the truck.
Compared to our last experience with a Mil-Spec Hummer, we wouldn’t necessarily call this better, but different and hugely entertaining. Throttling the M1-R produces quite a bit more noise than we remember in the previous M1, and most of it is good. The diesel engine emits a low, gravel-like rumble, but the turbo is the highlight, it sounds like a jet engine and gets louder and wilder as it rolls up. It takes quite some time for that excitement to take place, so the engine doesn’t feel super responsive in the city. It still comes around easily, but the big boost rush comes later. And what a kick. It hits hard and pulls longer than the standard bike. Putting the gear and size of the M1-R side by side is giggling.
As boisterous as the bike is, it feels even more woolly with handling and steering. The suspension setup is noticeably softer than the last Mil-Spec Hummer we’ve ridden. This was designed that way because the goal was to make it more comfortable. And indeed it is, although it also leads to more body roll. The steering of this truck also felt significantly less precise and required a fair number of steering corrections. You are definitely busier behind the wheel than most modern off-roaders. The good news is that the steering gear has a fast enough gear ratio and is light enough not to wear you out. In fact, it’s pretty easy to keep an eye on all corners of the truck, so maneuvering isn’t much more difficult than any other full-size machine.
With the amount of work put into the M1-R, it’s no surprise that it comes with a hefty price tag: $ 412,000. That’s a big increase from the base M1 price of $ 299,500, and much of that was thanks to the upgraded engine and custom selections like exterior color, interior and long-travel suspension. But the standard truck still gets the already excellent 500-horsepower engine, and it still gets the same switchgear and leather trim (albeit in less bold colors and more subdued stitching). So we don’t think you have to pay $ 400,000 to have the most fun in any way. Additionally, while we think Mil-Spec wouldn’t say “No” to a new M1-R if someone was willing to pay for it, Broekman told us they had no intention of doing another M1-R. They had fun working with the powerful engine, but they find it’s about as much as they can do while trying to keep the emissions standard (Mil-Spec trucks are legal in all 50 states), so they’ll most likely stick with to the basic engine setup. In fact, Broekman said the company is monitoring alternative fuel powertrains, including electrical systems that may be used in the coming years.
So the price is high, but there really is no such thing. It makes crazy noises, goes fast, and can do this just about anywhere. No Bentley or Lamborghini for the same money can come close to the same feeling.