Do you want better brakes? That sounds like one of those stupid questions that you hear on TV commercials that should be filed with “Do you want to live longer?” and “Do you like orphans?” Who the heck is going to say no? Certainly not me. Of course we want to live longer while liking orphans and having better brakes. And while we’re no experts in longevity or child care, we can tell you a bit about getting better brakes, now that we’ve learned a little more from Power Brake Service (PBS).
Since we think you can figure out for yourself why you’d want better brakes, we’re just going to dip right into how easy it is for most gasoline-burning vehicles to improve them.
Most gasoline-powered vehicles use a vacuum-assisted brake booster to generate more force (increasing pressure) in the power brake system. If you’ve ever driven a vehicle without power brakes, you know how much of an improvement a power-assisted brake system is. The vacuum brake booster is adequate for most vehicles, but for heavy-duty trucks and vehicles that don’t create enough vacuum for the brake booster, hydroboost brakes are often the choice for vehicle manufacturers.
Hydroboost power brakes work using hydraulic fluid pressure (fed from the power steering pump) to “boost” the force on the master cylinder’s brake fluid and therefore apply more force to the brake calipers (and subsequently more force on the rotors with the brake pads).
Both hydroboost and vacuum assist are power brake systems that multiply the force you can put on the brakes with your brake pedal, but hydroboost can create more force than a vacuum-assisted system—and without using an engine’s vacuum.
For us, we really had no choice but to step up to hydroboost brakes after installing a lopey camshaft on a V-8 engine. The amount of vacuum the engine made at idle was not enough to properly supply the vacuum brake booster, and the brakes in the truck got worse. After talking with PBS, we realized that all our problems could be solved by swapping on a hydroboost brake system in place of the original vacuum-assisted system that came stock on this particular truck.
How Does the Truck Brake Now?
The difference of the new PBS hydroboost system was immediately noticeable—and huge. The truck stopped much more quickly than before, and with more control. On top of that, the truck now holds itself on severely steep declines when off-road. The braking improvement of the truck is enormous.
The one downside we see? With a hydroboost system, you’re now scavenging off the power steering pump for power assist, inline of the power steering pump and the power steering box. A hydroboost system relies solely on the power steering pump to power both the steering box and the brakes. Theoretically, it should always work with no problem, but if you have a poorly working power steering pump then you should definitely upgrade that before adding a hydroboost system. If you’re thinking about adding a high-output aftermarket power steering pump, that couldn’t hurt either.