Today's custom truck has placed a huge burden on stock brake systems. Just as big rollers have increased the value of brake pad stocks, big brakes have been defeating brake dynamic effects of heavier wheels and tires. Aftermarket brake manufacturers have been building billet body brake housings, bigger, thicker, and slotted rotors, and multi-piston brake calipers for the on- and off-road market for years. Anyone who knows GM trucks, knows marginal brake systems became worse when antilock ABS was introduced.
Many of these brake systems provide a higher level of braking by using one or a combination of larger brake pads, larger rotors, and/or multiple piston calipers. The larger pad increases surface contact, and the larger rotor increases the brake's leverage arm. When more pistons are designed in the caliper, the piston volume sometimes goes beyond the stock brake piston volume. In these cases, the master cylinder and brake booster's ability to provide clamping pressure is compromised. When done properly, the compromise in clamping pressure is canceled out, because the added braking from added pad surface, or increased rotor leverage is worth more in stopping force than the loss in clamping force. The loss in clamping force will allow the rotor to drag across the increased pad surface and generate an increase in brake pad dust.
Some brake upgrades come with larger master cylinders and/or vacuum booster to accommodate the increase in volume necessary to move the calipers pistons. Large diameter brake boosters attached to a long snouted cylinder can become an eyesore mounted on the wall. In such cases, moving the vacuum booster and master cylinder is an option, if you don't mind a great deal of fabrication. The second option is to convert the brake system to hydroboost. In most cases, these kits cure what is slowing the stop. In the case of '90-'98 GM trucks, all of the above is the only way to get a grip on the rolling stock. We opted to put Stainless Steel Brake Company's (SSBC) Truck Stop Program to work by using its two-piston, bolt-on Truck Force 10 front-disc brake kit. Here's what we found.