Blazing A New Trail | 2002 Chevrolet Trailblazer
Chevy’s Latest SUV Makes A Great Platform
If you are a regular reader of OFF-ROAD, you know that we love S-10s and even have our own S-10 project—the Almighty Dime. These downsized Bow Ties are like the Rodney Dangerfield of the 4WD world: they get no respect.
When GM phased out the S-10 Blazer they replaced it with the Trailblazer. Despite body-on-frame construction, a strong engine, and a solid rear axle, the Trailblazer has even less aftermarket support than the S-10 Blazer it replaces. That didn’t stop Steve Carroll from building one for the trail though.
“I had a Toyota 4Runner with Chevy running gear,” Steve explains. “It worked OK, but it was just like everything else out there.” When he started to look for a four-door replacement for his growing family, Steve’s research led him to an ’02 Trailblazer. “The drivetrain is solid and reliable and the Trailblazer is big enough for four people but small enough to fit on the trails I like to run.”
Steve picked up the Trailblazer for cheap and intended to modify it from the start. Power comes from the factory Vortec 4200 inline six-cylinder that sends 275 hp to a 4L60E that received an auxiliary cooler and fan to keep it running cool. Steve monitors the temps in a gauge where the factory transfer case dial used to reside. That knob wasn’t needed once the dual transfer cases were added. The planetary from an NP241 is mated to an NP241 with a 32-spline output shaft and slip yoke eliminator with a Box 4 Rocks adapter.
From there things get really interesting. The factory suspension and axles were sent to the metal recyclers and 1-ton axles and leaf springs were used in their place. Why leaf springs? “They are simple, inexpensive, and work great for my needs,” Steve comments. All four corners are sprung by 52-inch Chevy springs that can be sourced from nearly any junkyard and work in conjunction with Rancho 9000 shocks. The springs move the axles out 6 inches at each end, which helps fit the 40-inch Nitto Mud Grapplers on Raceline Monster aluminum beadlock rims.
In order to live with the 103:1 crawl ratio and 40-inch Nittos, only 1-ton axles would do. The rear axle is an ’02 14-bolt that has factory disc brakes and was upgraded with 4.56 gears and a Detroit Locker from a CUCV truck under the Blue Torch diff cover. The front axle is a high pinion Dana 60 from a Ford. It has been fortified with 4.56 gears, a Yukon Spartan locker, Reid Racing knuckles, 35-spline Yukon chromoly axleshafts, Warn hubs, and a Blue Torch diff cover. Steering comes from a Toyota steering box that was tapped to work with a PSC hydraulic ram.
Steve built his own front and rear tube bumpers and added sliders from Trail Gear to protect the body. The front bumper was built to house a 10,000-pound winch and recovery shackles, while the rear holds a full-size spare and KC backup lamps. Steve built the rear bumper pivots with a shackle hanger kit he had lying around, and the whole thing folds down to access the cargo area. Inside he has a full cage and straps to hold down the Hi-Lift, spare driveshaft, CO2 tank, and spare parts and tools.
The end result definitely achieved Steve’s desire for a unique vehicle and illustrates that you don’t need to break the bank in order to have a capable wheeling vehicle.
So who’s going to build the first Trailblazer prerunner?
Who says leaf springs don’t flex? Steve runs 52-inch leaf springs at all four corners. These are junkyard springs from the rear of a ’73-to-’87 1/2-ton, making them inexpensive and easy to source if necessary. Steve just trimmed the fenders and built added lift into the spring hangers, allowing the use of these relatively flat leaf springs.
Although it was primarily built as a crawler, the six-cylinder makes plenty of high rpm horsepower to spin the 40-inch tall tires when necessary. Rolling stock consists of 40x13.5R17 Nitto Mud Grapplers wrapped around 17x9.5 Raceline Monster beadlock rims with steel beadlock rings. Both front and rear axles use factory eight-lug outers for maximum strength and minimal cost. Steve concedes that deeper gears would work better with the big tires, but the 4.56s fit his budget.