1972 GMC Jimmy - Off-Road Magazine

Must everything be so extreme? Not according to the responses we've had recently from you, our readers. In our July 2005 issue, Editor Phil Howell included a mail-in survey form in OFF-ROAD Notes asking for feedback. As of press time, the majority of those who responded listed trail riding/exploring and camping as their two top picks for what they did most often with their vehicles. We found it refreshing to realize that there's a large contingent of off-roaders who choose to use their truck for the very activity that got us out in the dirt in the first place: going exploring and having fun.

Scott Griesbach of North Ogden, Utah, has one of the cleanest, best-built "go exploring" rigs we've ever seen. "I've always liked the '69-'72 Blazers/Jimmys, so when I found this one, I bought it," Scott told us. "All I was going to do was put a 2-inch lift and 33-inch tires under it." We've found that mild-style buildup plans are quickly derailed once we learn about a few products or truck-building techniques that will get us farther down the trail. So it was with the '72 Jimmy. Scott put it succinctly: "Once I started, I couldn't stop."

1972 GMC Jimmy Passenger Side Rock Climbing

We've yet to come across a vehicle that's truly "done," but we can safely say that if the buildup remains in its current state, there won't be much left to do but change the oil, and decide which trail to explore next. This rig is good to go. The short list includes a set of 40-inch Goodyear MT/Rs, a Dana 60 front axle, a GM 1-ton 14-bolt full-floating rear axle, an Off-Road Design Doubler, ORD/Alcan leaf packs, Bilstein dampers, a Bestop soft top, and two child seats in the rear. Huh? With a "who's who and what's what" laundry list of trail-capable hardware and seating for Scott, wife Dani, and their two daughters, the Griesbachs are in for eons of adventure and exploring. There's something about a rig that drives down the freeway, takes on the toughest trails, has room for everyone in the house, and is equipped with bomb-proof running gear. Something extremely cool.

Keeping lift height to a minimum adds up to better handling on the street and more confidence when the trails begin to tilt. New suspension lifts the Jimmy a mild 4 inches, and the body was bumped only an inch skyward. To let the 40s fit with this combination of suspension and body lift, stealthy fender trimming was performed to let the suspension flex without contact between the sheetmetal and rubber. The lower lines of the body are coated in Rhino lining for scratch and rust resistance. Although the truck's body panels were straight and true when he purchased the truck, Scott was surprised at the amount of rust present on the floorboards. To remedy the rust, the body cancer was cut out and new body panels were welded into place. We don't know why the state of Utah continues to use salt on the roads in the winter when there are better ways of making the roads safer when the weather turns snowy. The salt does melt the snow and ice, which increases safety on the road. Salt isn't the only means of making the roads safer in the winter, though. Sand does a fine job of increasing traction on the roads during the winter months and doesn't corrode the undersides of vehicles the way that salt does. Savvy vehicle owners can fight back with products such as Rhino lining and POR-15, which was used to coat the Jimmy's framerails and the body's entire underside. Those who let the rusty cancer eat away at their vehicles end up at either a body shop to get new sheetmetal spliced in, or at a new-car dealer when the rust situation has gotten completely out of hand.

The OEM axles under the rig were a front Dana 44 and a GM 12-bolt rear. For stock to mildly bigger tires, the original axles are more than adequate. Add 40-inch tires and tough trails and you'll be breaking more axleshafts than you care to count.
The OEM axles under the rig were a front Dana 44 and a GM 12-bolt rear. For stock to mildl
A large part of this Jimmy's trail prowess is found in the 40-inch Goodyear MT/Rs mounted to Trail Ready's aluminum bead-locked 17x10-inch wheels. The balance of the rig's trail prowess is owed to Scott's holistic approach to building the vintage 'wheeler. The rest of the drivetrain and running gear were beefed to match the tires.
A large part of this Jimmy's trail prowess is found in the 40-inch Goodyear MT/Rs mounted
Fortunately, a Dana 60 from a 1-ton GM pickup bolts into place and is up to the task of the larger tires and tougher terrain. The pumpkin was filled with 5.13 gears and an ARB Air Locker. Turning the big tires is more accurate and much easier, thanks to an Off-Road Design crossover steering system and an AGR-built steering box and hydraulic assist.
Fortunately, a Dana 60 from a 1-ton GM pickup bolts into place and is up to the task of th

Rock sliders are another weapon in the Jimmy's trail arsenal. They protect the rocker panels and double as steps for the driver and passengers. These sliders tie into the frame for ultimate strength.
Rock sliders are another weapon in the Jimmy's trail arsenal. They protect the rocker pane
A low-profile component that's high in importance is the Off-Road Design Doubler transfer case setup. The Doubler puts an NP 203 range box in front of the stock NP 205 transfer case. Using the Doubler, drivers can select the stock Low range or a combined Low-Low range by shifting both the NP 203 and NP 205 into their Low ranges.
A low-profile component that's high in importance is the Off-Road Design Doubler transfer
Although old-style open-channel frames are flexy flyers, their design makes bolting on additional crossmembers an easy task. Power is transferred from the NP 205 to the Dana 60 and GM 14-bolt through a pair of Tom Wood's Drive Shafts.
Although old-style open-channel frames are flexy flyers, their design makes bolting on add

ORD/Alcan springs bolt into the stock hangers and swing on ORD front shackles and ORD-flipped stock rear shackles. Bilstein's 5125 14-inch stroke shocks feature tuned damping and attention to detail that's in keeping with the company's reputation for high-quality dampers throughout its product lineup.
ORD/Alcan springs bolt into the stock hangers and swing on ORD front shackles and ORD-flip
Look to the left of the urethane bumpstop and you'll see further evidence that this rig has been built correctly. Countless suspension systems are bolted onto trucks without a second thought to the often-needed brake line modifications. A simple drop bracket lets the stock rubber brake lines safely move in sync with the suspension.
Look to the left of the urethane bumpstop and you'll see further evidence that this rig ha
We normally don't pay attention to the underside of a hood, but we usually don't see this level of functional attention to detail paid to this component. Scott did most of the work himself, at home in his garage.
We normally don't pay attention to the underside of a hood, but we usually don't see this

While the GM front Dana 60 is pricey in the wrecking yards, the GM 14-bolt full-floating rear axle is much more common and that much cheaper to buy. This heavy hitter is beefy, right down to its dual-crosspin differential. A Detroit Locker was added to the rearend for no-fuss traction.
While the GM front Dana 60 is pricey in the wrecking yards, the GM 14-bolt full-floating r
Multiple thin leaves with even spacing and anti-friction pads are signs of a high-quality leaf pack. ORD shackles with greaseable bolts are also friction fighters.
Multiple thin leaves with even spacing and anti-friction pads are signs of a high-quality
We long for the days when engine compartments were this spacious and uncluttered. An ubiquitous 350 V-8 motivates the big blue Jimmy, aided by a few sensible bolt-ons. An RV cam provides horsepower and torque curves conducive to both freeway flying and trail riding. An Edelbrock aluminum intake manifold is topped by a matching Edelbrock Q-Jet carburetor and breathes through a dust-fighting K&N air filter. Ceramic-coated headers exhale into a Race Magnum exhaust. An HEI ignition ignites the fuel/air mixture. Aft of the 350 is another 350: GM's Turbo 350 automatic. This is a proven drivetrain combination that's easy on the wallet when it comes time to purchase parts.
We long for the days when engine compartments were this spacious and uncluttered. An ubiqu

Flipping the rear shackle with an ORD bracket turns the stock tension shackle into a compression shackle and lifts the rear of the truck 4 inches. One-and-a-half-inch lift springs were used in the rear, along with a 1-inch-rate add-a-leaf. This approach to rear suspension building gives a good ride and minimizes U-joint-killing spring wrap.
Flipping the rear shackle with an ORD bracket turns the stock tension shackle into a compr

In addition to the full rollcage that ties into the frame, Scott fabricated this rear bumper/tire-and-gas-can carrier combo. The owner is a mechanical engineer, and the sheer volume of owner-installed and owner-fabricated upgrades on this rig proves that he understands not only the theories, but the execution as well.
In addition to the full rollcage that ties into the frame, Scott fabricated this rear bump
Why show a pair of child safety seats? Because we think there's plenty of room in the off-road world for trucks that can 'wheel and take the whole household along for the ride. Trail riding family-style adds up to both quality and quantity time.
Why show a pair of child safety seats? Because we think there's plenty of room in the off-
The interior was left largely original and intact. The stock seats were reupholstered and the floor was rolled with Herculiner. Fuzzy dashboards and billet aluminum flame trim? Scott doesn't need that, and we don't, either. A Sony CD player and four 6x9-inch Sony speakers were installed by the owner, while the Bright Blue Metallic paint was applied by Perk's Autobody of Clearfield, Utah.
The interior was left largely original and intact. The stock seats were reupholstered and