TTC 2013 - 1977 GMC K15 Sierra Grande

John Retzloff's Silver Bullet Sierra

Jeremy CookPhotographerAgustin JimenezPhotographer, Writer

John Retzloff and Ken Retzloff finished Top Truck Challenge in First Place in their 1977 GMC K15 Sierra. Their consistency as well as the fact that they communicated and worked so well with each other throughout all the grueling events is what earned them top honors at this year's Top Truck Challenge. Where others struggled, the Retzloff's made up a lot of ground on the rest of the competitors and never looked back.

John had been very consistent throughout the week but he went all out on the Tank Trap despite his snorkel coming loose and landing in the water, John reached out and grabbed it - shoving it in the cab to keep it clear of the water. The Retzloff's worked very well together and Ken worked his tail off to help his brother John get through the challenges each and every day and were able to winch the truck out of bad situations. Although they were both able to get the GMC very close to the finish in the Tank Trap, they ended up running out of time just a few feet from the finish line. One of the really cool things about John’s truck is that it was propane powered which means it was likely the most environmentally friendly rig in town.

Tech Sheet
Truck: 1977 GMC K15 Sierra Grande
Frame: Stock Engine: 454 c.i. V8 running on propane
Drivetrain: TH400 automatic, Northwest Fab Black Box NP205 T-case with 2.71:1 gearing, Dana 60 front differential with Ox Locker, 14-Bolt rear differential with a Detroit Locker, 4.88 gears
Suspension: 52-inch Chevy leaf springs in front, 63-inch Chevy leaf springs in rear, 12-inch stroke Rancho RS9000X shocks all around
Wheels & Tires: 20x12-inch Stazworks Beadlock wheels wrapped in 46-inch Mickey Thompson Baja Claws