2007 Chevy Silverado - Four Wheeler Magazine

2007 Chevy Silverado - Raised Right Ken Brubaker Senior Editor, Four Wheeler

The 2007 Chevy Silverado is exceptionally refined, delightfully comfortable, and more than adequately powered. But for all of these good things, those of us who travel off-highway may find that it could use some help in certain areas. Take, for instance, its very low-hanging front fascia that can suffer a brutal Bobbit-style removal faster than you can say "Honey, what's up with the scissors?"

Rancho has responded quickly to Chevy's new 1/2-ton by unveiling the first aftermarket suspension kit for the new Silverado. One of the things it does is get that troublesome front fascia further away from terra firma. A lot further, actually. Rancho doesn't publish the lifted height of this kit; they just refer to it as the Rancho Silverado/Sierra Pickup Suspension System. We found that the kit generates approximately 5 inches of lift.

Our friends at Attitude Performance in Arlington Heights, Illinois, invited us to observe the installation of the kit on a customer's Silverado Crew Cab Z/71. What follows is an overview of how the major components of the kit install so you can see what is included and how it works.

PhotosView Slideshow Not only are the Silverado's off-highway capabilities increased with the addition of the Rancho kit, the lift combines nicely with the truck's styling to create a muscular visual stance. The kit includes all of the needed components and hardware, but shocks are extra. We installed a set of Rancho RS 9000X nine-position adjustable shocks. Note that the kit includes new knuckles and a one-piece subframe. 1 After the steering knuckles, shock absorbers, halfshafts, and lower control arms are removed, work begins to remove the front differential. First, a crossmember is removed and discarded, and then a reciprocating saw is used to cut off the driver-side crossmember bracket. This is removed to make room for the differential once it is lowered. This is the only cutting required to install the kit, and the instructions detail where to make the cut. The diff is then removed from the vehicle. 2 A pair of differential drop brackets are then installed using the included hardware. These brackets lower the diff, and Rancho says they're also designed to correct the pinion angle for minimized driveline vibration. 3 The differential is then reinstalled in the vehicle and the driveshaft is reattached. The kit does not require any driveshaft modifications, nor any exhaust mods, for that matter. 4 After enlarging the inside corners of both factory lower-control-arm front brackets with a round file, the one-piece subframe can be bolted into the OE lower-control-arm frame brackets as well as at two other points. This subframe will act as the new mount for the factory lower control arms, which are installed next. 5 Using a spring compressor, the coil springs must be removed from the OE front shocks and transferred to the new Rancho RS 9000X shocks. We found that placing the jounce bumper on the new shock shaft and then feeding the shock into the spring assembly works much better than trying to feed the shock shaft into the jounce bumper while it is in the spring assembly. 6 Here's how the completed coilover-shock assembly looks after it has been installed in the vehicle. 7 The hubs, splash guards, and ABS brackets are transferred to the new Rancho knuckles. The kit uses spacers between the axleshafts and the differential flanges to compensate for the increase in lift. Here you can see the front passenger side with the axleshaft and knuckle reinstalled, minus the brake rotor, caliper, and tie-rod end. 8 The sway bar must also be lowered. This is accomplished via sway-bar drop brackets that attach to the framerails at the original sway bar location. 9 After the brake rotors and calipers are reinstalled, the stock brake lines are removed and replaced with extended-length DOT-certified brake lines and the brakes are bled. 10 Rancho says that the new high-clearance aft braces maximize ground clearance and provide additional strength to the subframe during severe off-highway use. They include bushings and sleeves. Some vehicles may require that the corner of the factory skidplate be cut to avoid contact with the aft brace bracket. PhotosView Slideshow 11 Lifting the rear of the Silverado is a pretty standard affair. Each rear leaf-spring pack is augmented by a single add-a-leaf and new riser block. After these items are installed, the leaf packs are reassembled, new U-bolts are installed, and the new shocks are bolted on. 12 The rear of the vehicle is completed when the new bumpstops are installed and the new brake-line bracket is bolted to the rear differential. 2007 Chevy Silverado before Photo 9283593 Before 2007 Chevy Silverado after Photo 9250939 After

With features like only one frame modification, a one-piece subframe assembly, and new knuckles, the kit installed easily and relatively quick. The owner of this rig chose a set of 325/50R22 (35x12.50R22) Nitto Terra Grappler A/T tires, which are slightly larger in both diameter and width than the maximum recommended size of 315/70R17 (34.5/12.00R17). The owner also chose a wheel with a 6-inch backspacing instead of the recommended 5.5-inch backspacing. The result on our tester was some front tire rubbing that will require some trimming.

Rancho says that the kit preserves OE geometry for easy alignment, and they weren't kidding. After installation, and before front-end alignment, we were surprised to find that the truck tracked straight down the road. As expected, the ride was stiffer than stock. We feel this was mostly due to the lack of shock-absorbing sidewall on the big 22s. We would've chosen to stick with a 17-inch wheel or maybe upgrade to an 18-inch wheel so we could fit bigger brakes, but hey, it wasn't our rig. We didn't experience any bumpsteer during our short testdrive.

2007 Chevy Silverado before Ramp Photo 9283599 Before 2007 Chevy Silverado after Ramp Photo 9283602 After

Before the install, the stock 143.5-inch-wheelbase Silverado traveled 51 inches up a 20-degree RTI ramp to earn a score of 355 points, and we had to assign a person to manually bend the lower air dam upwards so we didn't rip it off just getting on the ramp. After the install, the Silverado traveled 55.5 inches up the ramp to earn a score of 387 points, and the lower air dam easily cleared the ramp.

Speaking of the air dam, which is the lowest point on the front fascia, before the install it rode an approximate 9.5 dismal inches above the ground. After the install, it rode an approximate 17.75 inches above the ground, which is clearly a very welcome improvement off-highway. Rear bumper-to-ground height improved from approximately 20.5 inches to 27.5 inches. All these numbers were taken before any settling had occurred in the suspension and with the 35-inch Nitto tires.