Hydratech - Power Assist Unit - Boost For Your Brakes

2001 Gmc Sierra Hydratech Braking Systems Front Angle

Power is fun, sexy, and one of the first desires for all hot rodders and custom truck enthusiasts. It takes your breath away and it helps knock out the cobwebs in your head after a long 9-5. Power can also be dangerous, especially if you accelerate so fast that your brakes can’t slow you back down. Out of control with you holding on for dear life, your truck can easily be turned into a 5,000-pound missile if you don’t plan ahead. As a wise man once told me, “Plan ahead, it wasn’t raining when Noah built the ark.” If you’ve been wondering how to make your truck safer, stop better, and keep yourself out of precarious situations, we have the solution for you—hydraboost.

Used in diesel truck and military applications for decades, hydraboost uses hydraulic pressure created by the power steering pump to force the brake fluid to each corner rather than vacuum pressure created by the brake master cylinder power booster. This setup is perfect for truck guys who are running superchargers, turbos, or even high-lift cams where constant vacuum isn’t always guaranteed at slower speeds or sudden stops. This upgrade works on trucks equipped with factory or performance brake kits, and it can be used with four-wheel-discs or disc/drum setups.

For Project Novakane, our in-house performance truck, the Stillen/AP Racing big brakes were stopping the 4,300-pound truck with ease, however, during sudden high-speed stops, the MagnaCharger supercharger wasn’t providing enough vacuum pressure to support the power brake booster. This caused several panic stops because we had our foot on the floor and the truck wasn’t coming to a complete stop. After searching for a viable upgrade, we came across Hydratech Braking Systems. As one of the leaders in the hydraulic power assist world, we ordered a bolt-on kit specifically designed for ’99-’06 GM fullsize trucks. The install was straightforward, using only common handtools, and the end results were quite impressive. One of the great things about this upgrade is big brakes aren’t required, as the Hydratech is compatible with factory brakes, as long as you upgrade your hoses to stainless braided. Check out the install, and if your truck could use some better brakes, give Hydratech a call.

1. The first step in making sure our ’04 GMC Sierra stopped on a dime was to remove the supplemental brake assist unit on the passenger-side of the booster. This unit is basically an extra vacuum pump designed to kick on if vacuum drops below 6 in/Hg and turns off at 9 in/Hg. Despite its best efforts to supplement the brake booster, a little pump can only do so much when bringing a 4,300-pound truck to a halt.
1. The first step in making sure our ’04 GMC Sierra stopped on a dime was to remove the su
2. After removing the two 15mm nuts on each side of the master cylinder, it was pulled free from the booster and set aside. It’s worth noting that the brake lines were not removed from the cylinder, which keeps air out of the brake system.
2. After removing the two 15mm nuts on each side of the master cylinder, it was pulled fre
3. Crawling underneath the dash, the four 15mm nuts that retain the brake booster to the firewall were removed. Being bent like a pretzel under the dash wasn’t very comfortable, but it was necessary.
3. Crawling underneath the dash, the four 15mm nuts that retain the brake booster to the f

4. We then disconnected the booster rod from the brake pedal with a flat screwdriver and pulled the booster free.
4. We then disconnected the booster rod from the brake pedal with a flat screwdriver and p
5. Taking a look at the Hydratech hydraulic power assist unit, the kit came with everything we needed to complete the install, including: high-pressure power steering lines, fittings, new brake pedal connector, detailed instructions, and hose clamps for the low-pressure hose.
5. Taking a look at the Hydratech hydraulic power assist unit, the kit came with everythin
6. Using the supplied hardware, the new hydraulic power assist unit was bolted to the firewall.
6. Using the supplied hardware, the new hydraulic power assist unit was bolted to the fire

7. The supplied brake pedal connector is adjustable to get the perfect fit. Once we had the rod length at the right length, we secured it with the original locking tab.
7. The supplied brake pedal connector is adjustable to get the perfect fit. Once we had th
8. We could then bolt our factory master cylinder onto the power assist unit with supplied Allen hardware.
8. We could then bolt our factory master cylinder onto the power assist unit with supplied
9. As you can see, the Hydratech unit looks as good as it functions thanks to the solid billet mounting flange, black powdercoat finish, and quality hardware. Getting rid of that big and bulky power booster off of the firewall sure helps make the engine compartment look cleaner.
9. As you can see, the Hydratech unit looks as good as it functions thanks to the solid bi

10. Per the Hydratech instructions, we inserted the appropriate brass fitting into the power steering pump high-side location. This will ensure the new fitting seals properly to the pump.
10. Per the Hydratech instructions, we inserted the appropriate brass fitting into the pow
11. Once the proper length of the high-pressure hose was determined, the hose was cut, the sheathing slid back, and the brass ferrule slid onto the Teflon lining. The hose fitting was then lubed up and slid onto the hose. Using a pair of 11/16-inch wrenches, it was tightened down and the hose was inserted into the power steering pump outlet. That hose was then connected to the power assist unit.
11. Once the proper length of the high-pressure hose was determined, the hose was cut, the
12. Coming out of the high-pressure side of the power assist unit, the other high-pressure hose was made up and inserted into the high-pressure side of the rack-and-pinion.
12. Coming out of the high-pressure side of the power assist unit, the other high-pressure

13. Here, you can see the view from underneath with the two high-pressure lines connected to the power assist unit and the rubber return line going down to a T-fitting that runs to the power steering pump, rack-and-pinion, and the factory cooler.
13. Here, you can see the view from underneath with the two high-pressure lines connected
14. To really get a true comparison of the new brake fluid pressure, we used this brake pressure gauge kit from SSBC and pumped the brakes on a vacuum booster-equipped 2001 Chevy Silverado. At idle, the vacuum booster could only muster a maximum of 700 psi with a constant rate of 550 psi. That doesn’t give us much confidence when pushing the brake pedal, big brakes or not.
14. To really get a true comparison of the new brake fluid pressure, we used this brake pr
15. Once the gauge was connected to our Hydratech-equipped brakes, we saw a max pressure of 2,000 psi with a constant rate of 1,800 psi. That’s an amazing amount of line pressure providing extra clamping force for our performance truck.
15. Once the gauge was connected to our Hydratech-equipped brakes, we saw a max pressure o

16. With that much pressure going to each corner, our rear brakes were locking up too early and bringing the rear of the truck around during hard braking. To equal out the fluid distribution, we installed this brake proportioning valve from Wilwood. It should also be noted that using stainless braided or hard lines is needed when installing a hydraboost unit, as the soft rubber hoses from the factory may be worn and cracked, which could cause a leak or brake failure at such high pressures.
16. With that much pressure going to each corner, our rear brakes were locking up too earl

From the Driver Seat

Brakes are one of the biggest areas where you don’t want to skimp, and thankfully the Hydratech kit was topnotch, both with its materials and ease of installation. Other than joining the fittings to the hoses, everything was a breeze. After several autocross sessions, the extra use of our 150,000-mile power steering pump did take a toll and we had to replace the power steering pump. Looking back, we should have done that when everything was torn apart anyways. Novakane stops with intensity now and the only issue we had was the rear brakes getting more bite from the added fluid pressure, but the Wilwood proportioning valve fixed that. Now, no matter what RPM we’re at, the race truck easily comes to a halt.

Your Questions Answered
Degree of Difficulty:	Mechanical Ability Needed
Time Spent Working:	5 hours
Tools Needed: 13mm and 15mm deep sockets, 10mm Allen socket, 3/8-drive ratchet, flat screwdriver, 9/16 and 5/8 flarenut wrench, torque wrench
Parts Used:
Hydratech Braking Systems Level III hydraulic brake assist system 3545	$845.00
SSBC Sure Stop brake pressure gauge kit A1704	$49.95
Wilwood Brakes proportioning valve 260-10922	$45.30
Total:	$940.25
(prices from manufacturers and do not include tax or shipping)

SOURCE
SSBC Performance Brake Systems 11470 Main Street Clarence NY 14031 800-448-7722 www.ssbrakes.com	Hydratech Braking Systems 2650 McCreary Rd Lebanon TN 37090 1-615-449-8261 http://www.hydratechbraking.com/
Wilwood Brakes 4700 Calle Bolero Camarillo CA 93012 805-388-1188 www.wilwood.com