Inconspicuous 1994 GMC Suburban 4x4

Inconspicuous Gmc Suburban Rock Crawling

It all started when Tony Lorenzo of Grass Valley, California, bought a GMC Suburban 2500 from a friend for his wife to drive. For two years it was a stock, reliable grocery-getter. Eventually it was replaced by a new car and it was at this point Lorenzo had an epiphany. He decided to build the “ultimate family wheeler” using the Suburban as his foundation.

Inconspicuous 1994 Gmc Suburban Going Off Sand Dune

To Lorenzo, an electrical contractor, the definition of ultimate family wheeler clearly doesn’t mean a flashy, unlimited budget, over-the-top build. What it means to him is taking a massive vehicle that’s capable of hauling a number of people and gobs of gear and modifying it to handle super tough trails. “Once I started, it took only three weeks with the help of WFO Concepts cutting brackets and supplying parts,” Lorenzo says.

The exterior of the Suburban gives little indication of the trucks true capabilities. Modifications are minimal, but functional. Up front it sports a garage-fabbed Baja-style bumper/skidplate made from 1¾-inch, 0.120-inch-wall material. It holds a trio of Kragen Auto Parts-sourced 7-inch-diameter HID lights to help illuminate the trail at night. Hidden behind the bumper is a Warn 8,000-pound winch in case Lorenzo gets the Suburban in too deep (Lorenzo was in the midst of finishing the winch install when we photographed the truck and hadn’t installed the fairlead yet). Protecting the lengthy rocker panel real estate is a set of Lorenzo-fabbed rock sliders made from 2-inch by 4-inch, 0.250-inch-wall material. The Suburban rolls on 40x13.50 Goodyear MT/R tires mounted to 17x9 Pro Comp steel wheels.

The exterior of the Suburban gives little indication of the trucks true capabilities. Modi

Since the whirlwind garage buildup, the big, flexy Suburban has successfully negotiated a variety of tough trails usually dominated by short-wheelbase rigs. “It’s amazing the looks you get from people when you’re on Fordyce or Rubicon,” he says of the long-wheelbase SUV.

The Details
General
Owner/Hometown: Tony Lorenzo, Grass Valley, California
Vehicle/Model: 1994 GMC Suburban 2500
Estimated value: $30,000
Engine
Type: GM 454ci V-8
Aspiration: TBI, custom exhaust w/Magnaflow muffler
Output, hp/torque (estimated): 300/300
Drivetrain
Transmission: 4L80E
Transfer case: Atlas 3.8:1, 2-spd
Suspension
Front: Chevy ½-ton leaf springs, Rancho RS9000XL shocks
Rear: Leaf springs, WFO Concepts shackle flip kit and torque arm, Rancho RS9000XL shocks
Axles/Differentials
Front: Ford Dana 60, PSC steering box, WFO Concepts high-steer arms, drag link and tie rod/ARB Air Locker
Rear: GM 14-bolt/ARB Air Locker
Ring and pinion: Sierra Gear 5.38:1
Wheels: 17x8 Pro Comp steel
Tires: 40x13.50R17LT Goodyear MT/R

Helping to protect the belly of the beast is a large skidplate made from 1⁄4-inch-thick steel. Shielded by the skidplate is an Atlas two-speed transfer case with 3.8:1 low-range ratio, which gives the big Suburban excellent crawlability for slow-speed trails like the Rubicon. Sprouting from the ’case are a pair of custom driveshafts. The front ’shaft is 1350 CV-equipped and both ’shafts are fitted with 1350 U-joints.
Helping to protect the belly of the beast is a large skidplate made from 1⁄4-inch-thick st
Safety for the trucks occupants is enhanced via a five-point rollcage made from 1 3/4-inch-diameter, 0.120-inch-wall DOM tubing. Other interior mods include switches for the ARB Air Lockers and a custom console for the Atlas transfer case twin-sticks.
Safety for the trucks occupants is enhanced via a five-point rollcage made from 1 3/4-inch
A fullsize spare tire is secured in the cargo area behind the third row seating.

Knowing full well that the stock IFS would never hold up to the trails he planned on running in the Suburban, Lorenzo replaced it with a leaf spring suspension and solid axle. He used a prototype WFO Concepts straight axle conversion kit, Chevy 1/2-ton rear-application leaf springs, 12-inch-travel Rancho RS9000XL shocks, and a modified and flipped sway bar (which was removed in these photos). A limiting strap runs from the differential housing to the Suburban’s chassis to keep the flexy suspension from overextending and causing bind in the driveshaft yoke. The axle is a Ford high-pinion Dana 60 with Sierra Gear & Axle 5.38:1 cogs, an ARB Air Locker, and Warn lockout hubs. The axle is located via a 1 1/4-inch-diameter, 0.250-inch-wall Panhard bar. The big 37s are pointed by a WFO Concepts high-steer system with PSC steering box and a Ford pitman arm. The WFO drag link and tie rod are both made from 1 1/2-inch-diameter, 0.250-inch-wall DOM tubing.
Knowing full well that the stock IFS would never hold up to the trails he planned on runni
The rear axle is a 14-bolt that has been regeared to 5.38:1 ratio using Sierra Gear & Axle components. It has also been fitted with Chevy 1/2-ton disc brakes using WFO Concepts brackets, and it has an ARB Air Locker. The leaf springs are the original units, but Lorenzo added a WFO Concepts shackle flip kit and a WFO torque arm made from 2-inch-diameter, 0.250-inch-wall material. A pair of Rancho RS9000XL shocks round out the suspension.
The rear axle is a 14-bolt that has been regeared to 5.38:1 ratio using Sierra Gear & Axle
The stock TBI 454ci V-8 engine runs great and produces plenty of horsepower and torque, so Lorenzo left it mostly alone for the time being. He did install a custom exhaust system with Magnaflow straight-through muffler to help the engine breathe a bit better. Fuel is stored and supplied by the stock 44-gallon fuel tank. Flanking the engine is the stock 4L80E automatic transmission.
The stock TBI 454ci V-8 engine runs great and produces plenty of horsepower and torque, so