Going fast is sexy. The smell of tire smoke, sounds of a chest-thumping V-8 roar, and the smile you get when you leave an inferior car at a stoplight-it's a beautiful thing. Power will, however, rarely save your life. Whereas we don't spend as much time talking about safety as we do adding more ponies, when it comes time for our own daily drivers and projects alike, we don't skimp on brakes. When researching brakes for our '04 GMC Sierra, dubbed Novakane, engineering, reliability, and street/track performance were key areas of concern. With our plans to autocross and road race this truck, the brake system upgrade had to bring our 4,300-pound truck to a neck-snapping halt.
| 2004 GMC Sierra Brake Upgrades test Facility
NASCAR race cars create some of the most extreme conditions for braking systems, with insane temps, incredible heat cycles, and caliper clamping forces pushing components to their peak. Once we found out that 38 out of 43 NASCAR teams trust AP Racing for their cars, we figured they could easily stop our beat-up, old work truck Sierra.
Stillen is the exclusive distributor for AP Racing in the United States and after a phone call, we learned the brakes needed for our '04 GMC were in stock and ready to be bolted on. The AP kit included aluminum six-piston calipers and 14.25-inch drilled, slotted, and vented rotors up front and four-piston calipers with 14-inch rotors out back. The rear rotors incorporate the factory parking brake drum, and both front and rear calipers come with Goodridge stainless braided hoses for superior brake fluid pressure and zero swelling under load. A big perk about this kit, it literally bolts right on with front and rear caliper brackets, and with the factory rear disc-equipped trucks from '99-'05, you don't have to pull the rear axles to complete the install.
We went to Stillen for a test fitment and took these install photos there, thinking that we wouldn't run into any unforeseen problems while testing out at the track that we showed you last month. Unfortunately, we learned the hard way at the track that the new McGaughy's spindles required some modifying to fit the AP caliper bracket. After the brief delay, we went back to our test facility for extensive brake testing, where we may have briefly stopped the Earth's rotation. Follow along as we show you how we installed the brakes and how big of an improvement the new AP Racing big brakes from Stillen made on our project truck.
High-Speed Brake Testing
Rather than test the truck from 60 mph, we hit the 'whoa' pedal at 80 mph, after all, do you really drive 60 mph on the freeway? Factory braking performance was dreadful, as a combination of grooved rotors and newish pads made for chassis vibrations when stopping and a weak pedal. After bolting on the 20-inch wheels and tires to the Sierra, the sticky Nitto tires actually improved the stopping distances, which confused us at first, but then we released the overall weight of the new wheels and tires wasn't much heavier than our OE combo.
GM touted the redesigned '99+ fullsize trucks as having the best brakes in their long history of building trucks. That's nice marketing hype, but GPS data acquisition doesn't lie and the new AP Racing brakes are the double-D cups to the OE's training bra. We weren't surprised to have better overall stopping power, after all, that's what we expected from a company with a rich racing heritage, but what did surprise us was the pedal feel. Without being touchy, the brake pedal is now very linear with minimal inputs doing an impressive job of bringing the 4,300-pound truck to a standstill. As expected, the aggressive brake pads are heavy on the dust, which provides us another excuse to wash the wheels/tires more often. This upgrade was expensive, but unlike in many cases, you actually get what you pay for from Stillen. With the AP kit bolted on, we made several 80-0 mph test runs and came away wit an average of 226 ft, more than 144 ft than better than stock. That's equivalent to stopping in only 5.56 school buses or basically stopping before going through an entire intersection and saving the lives of more than 350 kids in those buses. Also, the green AP heat paint that was applied to the stock rotors burned white, meaning they exceeded 430 degrees Celcius during hard braking, but the new AP rotors didn't burn through the green paint. This translates into the drilled holes and vents doing their job by keeping the rotor surface cooler, longer. If safety and performance are high on your list, bringing your truck to an immediate halt doesn't get much better than with AP Racing's bolt-on big brakes.
YOUR QUESTIONS ANSWERED
Time Spent Working: 5 Hours
Degree Of Difficulty: Beginner
Tools Needed:
18mm socket, 15mm socket, 1/2-inch flare nut wrench, 9/16-inch flare nut wrench, 10mm Allen socket, 12 mm Allen socket, torque wrench, blue Loctite, zip-ties
Parts Used:
AP Racing front big brake kit AP1545R
$2,516.18
AP Racing rear big brake kit AP1550R
$1,500.00
AP Racing Super 600 brake fluid 15 601600
$19.95 (x3)
Total: $4,076.03
(prices from stillen.com and do not include tax or installation)
