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This D-Max Turned Out A Good Deal For All

Posted in Features on September 8, 2016
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Danny Giannini spent his early days racing motocross with his buddies, until he discovered off-road racing and pre runner trucks, that is.

He quit racing MX and immediately set out to build a 1400 truck. With some help from some local off road fabricators/friends and all the $$ his construction job would allow, he had his truck ready for their first race in 2006. But they only lasted a few miles. By 2008, however he brought home the MDR Class 1400 Championship. An accomplishment that Giannini is, rightly, very proud of.

He also began working under the guise of Giannini Metal Designs in Cherry Valley CA. After that season he set out to build a new racecar using lessons learned from the first truck. The result of three and a half years of labor would be a self-built TT; one that he would eventually trade to Austin Lessel for this Duramax Prerunner.

The 6.6l Duramax has been upgraded with an EFI Live DSP5 along with a custom aluminum intake built by Giannini Metal Designs who also made the 4-inch straight pipe exhaust. Other tricks include Garrett Stage 2 turbo, Fass lift pump and an EGR delete. The guys at PPE in Fullerton CA know a thing or two about big power diesels, and with the engine tuned by Corey at PPE, the result is 600hp with 820lb.ft. of torque. That’s a lot, so Alligator Performance heavily worked the Allison A1000 transmission to make that all of it gets to the AAM 11.5 Full Floater axle that was tabbed and trussed by Giannini Metal Designs. The gears are Yukon Gear & Axle 4.88’s, with the driveshaft work done by Banning Driveline of Banning CA. A pair of CBR trans coolers has been run in series to keep the Alison cool even during high desert temps.

The crew at Dirt Designs transformed the Chevrolet frame with a full front to rear 2-inch cage. The huge Dirt Designs equal length I beam frontend features Dirt Designs uprights with Dana 60 spindle snouts and hubs. A swing set steering with a Howe GM steering box and Howe ram assist spin the 39-inch BFG KR Projects that have been mounted on 17x9 Ultra Wheel 103 Beadlock wheels.

King 3.0 coil-over shocks that are mated with 4.0 King Bypass shocks providing the dampening for all of the 24-inches of wheel travel. Oddly, a set of 2010 Dodge calipers & rotors provides the braking up front.

There are GM brakes out back, but there’s also a Dirt Designs 4 link suspension system that again utilizes King Shocks and again they’re 3.0 Coil-overs and 4.0 Bypass shocks, but this time there’s 29-inches of wheel travel.

Concentrating on making the rest of the truck off road worthy, the interior is a work in progress, but the important stuff has been taken care of as the seats are PRP Podium units that utilize PRP 5.3 harnesses to keep all intact. A Rugged Radios intercom system ties in with the Icom Race Radio and a Lowrance 5C GPS system keeps everyone informed and in touch.

Proving that he’s multi-talented, Giannini spread the Avery Dennison Matte Grey Metallic vinyl wrap onto the various fiberglass pieces that have been added to the truck.

First is the Fiberwerx 99-06 to 2015 Extreme Conversion front clip that includes a GM grille & headlights. For the bed there are Fiberwerx 99-06 to 2015 Extreme Conversion bedsides that have been fitted with GM taillights. There’s little doubt that the truck looks great and that while it was nice when he received it, Giannini has done a ton of work to it himself, including not surprisingly a good deal of the fabrication and metal work.

But it was all a means to an end, as Giannini explains, “The Duramax really appealed to me because it is street legal, and has 4 seats which works perfect for my family and I.” And while we all love a good racecar, there are a lot of ways to be a winner.

A fair trade for a Trophy Truck, this 2006 Chevrolet Duramax powered pre-runner gives it’s owner a chance to take the family out for a fast desert spin.
The 6.6L Duramax provides plenty of power while the Dirt Designs and King shocks put it to good use spinning the BFG KR’s.
The soot inside the exhaust pipe tells all that a diesel resides within, while the Giannini Metal Designs setup itself is beautifully done.
A Garrett Stage 2 turbo, a Fass lift pump and an EFI Live DSP5 gives the 6.6l Duramax way more power over stock. Danny Giannini made the 4-inch straight pipe exhaust system.
Massive, equal length I-beams by Dirt Designs provide the basis for the front end. Other tricks include Dana 60 spindle snouts and hubs, swing set steering with a Howe GM steering box and Howe ram assist. Wheel travel is 24-inches.
More than up to the task of holding the Duramax up are the King Shocks, as 3.0 Coil-Over shocks are mated with 4.0 Bypass units.
Providing 29-inches of travel is the Dirt Designs 4-link rear suspension.
King Shocks are used out back too, and again they’re 3.0 Coil-overs and 4.0 Bypass units that fit perfectly in the Dirt Designs cage-work.
Giannini modified the Dirt Designs rear cage so that it now holds two of the BFG/Ultra wheel combinations and the jack is now handy to get to easily.
The fuel cell is placed mid-truck to give it good balance and protection.
Giannini trussed and tabbed the AAM 11.5 Full Floater so that the Duramax’s power wouldn’t cause any problems. The gears are Yukon Gear & Axle 4.88:1 while the driveshaft work done by Banning Driveline of Banning CA.
Lots of torque means the need for lots of stability for the driver, so PRP Podium seats and PRP 5.3 harnesses allows for a good grip.
The Dirt Designs cage is a monster and it’s clear that they didn’t hold back with the steel.
Ready to ride into the sunrise, the Duramax powered Chevy is all business, and by that Giannini means all fun for his family.


Garrett Turbo
Denver, CO 80216
EFI Live
Auckland, NZ, AK
Tulsa, OK
Fiberwerx Offroad Fiberglass
Santee, CA 92071
Ultra Wheel Company
Fullerton, CA 92833
PRP Seats
Murrieta, CA 1-951-894-
Rugged Radios
San Luis Obispo, CA 93401
Icom America
King Off-Road Racing Shocks
Garden Grove, CA 92843
Howe Performance Power Steering
Yukon Gear and Axle
CBR Performance

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