A 45:1 crawl ratio with helical gear-reduction hubs, a Central Tire Inflation System with 37-inch runflat bead lock wheels, a locking transfer case, locking front and rear differentials, four-wheel independent suspension, inboard mounted disc brakes, skidplates, rocker guards, and an auxiliary fuel tank. What could make the Hummer H1 better? How about a 6.6L Duramax turbodiesel engine with 300 hp and 520 lb-ft of torque? Throw in the heavy-duty, five-speed Allison transmission and you've got the best civilian Hummer ever: the H1 Alpha. General Motors decided to save the best for last, and then cancelled production of the H1.
Unlike the Hummer H2, (which is essentially a 3/4-ton Chevy Tahoe), the Hummer H1 is a truly unique off-road vehicle. It features a robust four-wheel independent suspension with coilover shocks and a track that's 3 inches wider than a pickup in the front and more than 5 1/2 inches wider in the rear. | 
For just $135,225, plus tax and registration, you can have an Alpha badge shining in your driveway-assuming an H1 will fit in your driveway. |
It's not your typical 300hp canyon-carver. The wide body of the H1 Alpha is great for stability, but it's easy to crowd other drivers on city streets and mountain roads. | |
One for the RoadBy the time you read this, the last Hummer H1 built for the public has already rolled off the assembly line. Since it's always fun to take a road trip and go camping with an old friend before they move away, we decided to spend some quality time with the H1 Alpha. We packed up the bed of our Flame Red open top Hummer, filled the fuel tanks, pointed it north, and followed the 101 freeway up the California coast. The Duramax was put to work as we pulled grades and snaked our way through San Francisco and up to campsites near the Oregon border. And, no, we did not get egged for driving the environmentalists' scapegoat through the Bay Area-although we did once get nailed by an egg while driving an H1 in Los Angeles a couple of years ago.
Thanks to the smaller (but still giant) transmission tunnel introduced in 2004, our passenger did not require medical treatment for a warped left ankle or knee after spending many hours in the front seat. In addition to the improved physical layout, the performance of the new drivetrain made driving the H1 much more enjoyable. Leaving from stop signs and accelerating onto freeways is much easier, and you can almost forget that you're driving a truck that weighs more than 7,000 pounds. After a week of driving it every day, you finally get used to the machine's width. You develop your braking technique to avoid the "Hummer-rock" (caused by the inboard disc brakes and the geared hub lash) when you come to a stop. And you stop noticing everyone you pass-checking you out as you drive by.
H1 Duramax TurbodieselA 2-inch body lift was required to fit the Isuzu/GM-designed 6.6L Duramax where the original 6.2/6.5L Optimizer used to sit. Hummer decided to install the LLY-coded engine, which is rated at 300 hp and 520 lb-ft of torque. That instantly gave the Alpha 46 percent more horsepower and 18 percent more torque than the last Hummer. This knocked three seconds off the zero-to-60 acceleration time, which is now 13.5 seconds. The towing capacity was also increased by more than 1,500 pounds. The Duramax greatly improved responsiveness both on- and off-road. Plus, the significantly improved fuel economy of the new engine combined with larger dual fuel tanks increased the range from 400 miles to about 570 miles per fill-up.
A 2-inch body lift was required to squeeze a Duramax into the H1. The engine used in the Hummer H1 Alpha carries the Regular Production Option code LLY (300 hp/520 lb-ft), unlike the latest GM pickups that have the more powerful LBZ engine (360 hp/650 lb-ft). The engine in the Hummer features a more shallow oil sump and pan to help the engine stay clear of the suspension and drivetrain. It also has a revised exhaust that exits on the driver side of the engine bay and a different power-steering pump than the LBZ. | 
Even though the H1 has a wide track and body, the frame is relatively narrow for improved torsional rigidity. Sliding over obstacles with high breakover angles is fairly painless since the framerails act as sliders while protecting the running gear tucked between them. |
Behold the heavy-duty Allison 1000 five-speed automatic transmission that replaces the four-speed 4L80E. The Allison name has become synonymous with diesel performance because it can be built to withstand up to 2,000 lb-ft of torque. In the H1 Alpha, you really notice the extra gear ratio and higher overdrive along with a 45:1 crawl ratio that's more than 20 percent better than the previous model. The Allison also has a tow/haul setting that adjusts shift patterns for the best performance when you're towing or hauling a heavy load. | 
The addition of the Duramax engine and the Allison transmission caused our Open Top H1 Alpha to weigh in at 634 pounds more than the same model from the previous year (the Wagon weighs 556 pounds more than the '05). Bridge trolls and hippies may not like the extra weight over the wheels, but the extra power of the Duramax will make drivers unaware of the added pounds. |
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