Bungee jumping, skydiving, roller coaster rides...it doesn't matter. Nothing compares to skimming across the desert floor at freeway speeds in a truck that weighs more than most tow vehicles. If you've ever ridden over whoops on a dirt road and loved it, you know where we're coming from. Just think about how much fun you had. Now imagine tripling your speeds and you'll know what it's like to ride in our prerunner Suburban.
Man loves speed, and no matter how thrilling you think a 100 to 1 crawl ratio is, it's never going to kick you in the ass like 420 hp, 4.88 gears, and enough suspension travel to make any road feel paved. Our '01-bodied Suburban built from a '73 GM truck frame was nearly two years in the making and uses a combination of components popular in rockcrawling, mud bogging, and desert racing. We knew the truck would have to take a beating and hold together for more than one trail ride at a time. We also knew the typical dual Dana 60 axle recipe wasn't going to cut it, and we set out to build a four-link rear and independent front suspension monster from the ground up.
Having worked with Off Road Unlimited in Burbank, California, over the years on large-scale projects like this, we knew that Maurice Rozo and his staff could put together exactly the kind of machine we had in mind, using only the highest-quality parts and fabrication work available anywhere. Now that we've taken it out for a few shakedown runs in the desert between L.A. and Las Vegas we can tell you the truck has been a success. Just imagine yourself climbing through the window Dukes of Hazzard style, strapping in to the five-point harness and slipping a helmet on over your head before you can flick the ignition on and hit the starter switch. Suddenly the Vortec 8100 fuel-injected big-block in marine trim roars to life. You pull the Jet TH400 into First gear, the rearend of the truck squats and you're flying down rutted roads in an adrenaline junkie's overdose dream. As your eyes tell you that you're about to eat it, the suspension, tires, and chassis scream, "Bring it on!" And then you remember this thing is just a windshield and some headlights away from being street legal! This truck is truly an awesome four-wheel-drive experience. We can't wait to take it on our first road trip. Keep an eye out for us. We'll be the silver blur screaming by you down the center median.
4WOR Pre-Runner Suburban
•Body: '01 Suburban sheet-metal with fiberglass front clip
•Chassis: '73 GM truck with 0.120-wall chrome-moly cage
•Engine: 8.1L (496ci) V-8
•Transmission: TH400
•Transfer Case: NP241
•Front Axle: IFS Dana 44, with Dana 60 outers, 4.88 gears, ARB, and custom CV-shafts
•Rear Axle: AAM 101/2-inch 14-bolt with 4.88 gears and Detroit Locker
•Front Shocks: 3-inch-diameter, 14-inch-travel King coilovers with reservoirs
•Rear Shocks: 3-inch-diameter King coilovers with reservoirs and 3-inch-diameterbypass shocks
•Tires: 37x12.5R17 BFG Baja T/A
•Wheels: 17x8 Alcoa with bead locks
When our 420hp, King-shocked, BFG Baja T/A-clawed road warrior is stripped of all its '01 Suburban skin, it still looks ready to tear the heads off all other SUVs in the grocery store parking lot. There are 8100 Vortec reasons to lay into the throttle and two extra seats to take your buddies along for the biggest E-ticket ride of their lives. | 
This is the view you are most likely to see of our Suburban if you come across it on the high desert plains of California or Nevada. Off Road Unlimited kept the rear of the wide-body Suburban open to increase airflow through the Griffin radiator, to ease tire changes, and to make fuel stops as quick as possible. A yellow Hella foglight is used under dusty conditions to keep Trophy Trucks from becoming impacted in our backs like a set of 800hp wisdom teeth, and a custom tube bumper protects us if we can't get out of their way. |
Suspension travel at all four corners is managed with Bilstein air bumps. These nitrogen pressurized cylinders control the last 4 inches of uptravel in the suspension and are mounted in adjustable sleeves that were TIG-welded to the front shock towers and held in place with Grade 8 bolts. | 
Originally the Suburban was set up with a four-wheel disc brake master cylinder without power assist, but it has since been upgraded to GM Hydro-Boost that uses power steering fluid pressure instead of vacuum for power assist brakes. The brake lines were routed using Goodridge braided stainless steel lines from Orme Brothers that go to two adjustable Wilwood proportioning valves mounted under the dash so the brakes can be dialed in on-the-fly for precise control. |
A Jet Transmission-built TH400 with a manual valvebody, a heavy-duty torque converter, and a Summit deep-sump cast-aluminum transmission pan backs the 8.1L big-block. Four-wheel drive comes from an NVG241 transfer case that's been equipped with a slip-yoke eliminator kit and bolted in with an abuse-proof transmission mount. High Angle Drivelines designed, built, and high-speed-balanced the bulletproof driveshafts that use 1410 Spicer U-joints to allow 36 inches of rear-wheel travel without the need for a CV-joint. While we're under the truck, notice the cooling lines; they're protected by the original '73 GM truck frame and plumb the engine coolant to the rear of the vehicle. | 
Should the big bad 'Burb ever land on its TIG-welded chrome-moly rollcage, the driver, co-pilot, and navigator are all secured in Mastercraft suspension seats featuring adjustable lumbar support and Pyrotect five-point safety harnesses. Note the handformed aluminum dash, center console, and interior panels that complete the cockpit. They keep dirt, heat, and water out of the passenger compartment without adding much weight. |
It's hard to get stuck when you're streaking across the desert at upwards of 100 mph, but should the Suburban wallow in a bottomless sandpit, the front suspension has been equipped with 935 CV-joints from McKenzie's Performance Products and custom half-shafts built by ORU. Currently the four-wheel drive is a part-time traction aid because the 20 inches of front suspension travel is capable of exceeding the operating range of the current system. Larger CV-joints with slip shafts are currently being tested to create a true all-wheel-drive package. In the steering department the Dana 60 steering knuckles have proven to be indestructible since ORU added chrome-moly plate reinforcements and tie rods made from chrome moly and 7/8-inch Aurora rod ends. | 
As hard as driver Maurice Rozo pushed the silver bullet, we barely ever saw the rear 14-bolt axle come off the ground. With 36 inches of suspension travel, King coilover and bypass shocks, and a custom-fabricated rear sway bar, the 37x12.5R-17 BFGoodrich Baja T/As stayed anchored to the ground and looked killer on Alcoa 17x8 wheels upgraded with black powdercoating and McKenzie's Performance Products bead locks. |
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