Hummer H2 Rancho Suspension Lift - Elevated

The Hummer H2 evokes a number of responses from people, ranging from envy to amusement to dislike. If you're a reader of Four Wheeler you know that we've tested H2s extensively, in both SUV and SUT forms, and we haven't been shy in pronouncing them to be some of the most off-highway-capable fullsize rigs available. They're designed with some of the best approach, departure, and rampover angles in the biz, and they come standard with an electric rear locker. All things us wheelers want and love. We fall into the envious category.

1. Here's the kit (RS6556)... 

   

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1. Here's the kit (RS6556) as it arrived. The owner of this rig chose the black finish, but the kit is also available in red. The H2 we lifted did not have the optional rear air-spring suspension, so new rear coil springs were included. For those H2s fitted with air springs Rancho offers a kit (RS6557) that includes aluminum air-spring spacers.

The aftermarket has responded to the H2 over the years, and we're not talking about chrome accessories, though there are most certainly enough of those things. We're talking about suspension kits that further enhance the H2's capabilities. One of those companies is Rancho Suspension, and this month we look at how its 4-inch kit for the H2 helps to modify the rig to make it an even better performer on the trail.

We know what you're thinking. You don't own an H2 and you never will. Well, this story may be relevant to you anyway because some of this suspension kit's architecture is similar to that found in other Rancho late-model GM light truck and SUV suspension systems. Rancho engineers like to say they're the "same parts, but different." For instance, the Rancho H2 subframe has similarities with the subframes used in other Rancho GM lifts. Another example is that the knuckles used in the H2 kit are the same used with the '01-'08 GM 2500 HD suspension system.

We installed this kit at Attitude Performance in Arlington Heights, Illinois, under a vehicle that had already been fitted with 37x15.50-20 tires. The vehicle had no lift, so the larger-than-stock tires were rubbing when the steering system was at full lock. The owner chose to install the kit to solve the problem. Here are the major components and installation highlights of the Rancho kit.

2. We began the install up...        read full caption 2. We began the install up front. After removing a number of components including the torsion bars, lower control arms, shocks, end links, steering knuckles, axleshafts, sway bar, and front differential, the driver-side crossmember/lower control-arm bracket was cut off to facilitate installation of the new subframe.	3. Once the bracket is cut...        read full caption 3. Once the bracket is cut off, a supplied box plate is welded to the inside of the lower control-arm frame bracket. It's then painted to inhibit corrosion.	4. Next, the upper mount is...        read full caption 4. Next, the upper mount is cut off from the front differential. Printed instructions with illustrations show how the differential should look when the process is completed.
5. A differential support...        read full caption 5. A differential support bracket is then attached to the front differential. Some differentials (like ours) have a boss that must be drilled out for one of the mounting bolts.	6. The front-differential...        read full caption 6. The front-differential assembly is then mounted to the new one-piece reinforced subframe.	7. It takes a couple of people...        read full caption 7. It takes a couple of people to lift the subframe/differential assembly into position due to its weight. The subframe mounts in the factory lower control-arm frame brackets. Ours bolted right in. With this assembly installed, the front driveshaft is reconnected.
8. At this point it's important...        read full caption 8. At this point it's important to ensure that the grease fitting on the steering relay rod does not contact the left side of the differential as the steering system is cycled. We had to remove a bit more material from the differential case to eliminate contact.	9. Next up are the new extended...        read full caption 9. Next up are the new extended cast steering knuckles. Here you can see one of the new knuckles (left) compared to the stock knuckle.	10. The new knuckles are installed...        read full caption 10. The new knuckles are installed to the upper and lower ball joints as shown here and then the O-rings, splash shields, ABS cables, hub and bearing assemblies, brake rotors, and calipers are installed on each side of the vehicle.