Engine/Transmission (1998.5 - 2002) Hydro-Boost Brake Booster Removal Procedure

[OakViewJeff]

This step-by-step procedure will help you get your failed hydro-booster out of your 2nd Gen truck. I used the procedure posted by firefighter_2000 and am adding pictures to help clarify the work. I replaced my hydro-bootser, while on the road in New Mexico, with a Napa reman by A1 Cardone. Unfortunately the first replacement failed to work (no fluid from the return line), so I had to the job twice! I'm always sad to hand over my original parts for remanufactured units (transmission, starter, alternator, and now hydro-booster).

Recommended Tools and Supplies
- 3/8" Drive, 9/16" Deep Socket, Universal, Short Extension
- 1/2" Drive, 15mm 12pt socket, Universal, Short Extension
- 18 mm Flare Nut Wrench
- Pliers, Flat Screwdrivers
- 3/8" ID Power Steering Hose x 5ft
- 1 Quart Power Steering Fluid
- Black Latex Gloves
- GoJo Wipes

Removal Procedure

1. Disconnect ground cable from batteries. Remove stored pressure in the hydro-booster by depressing the brake pedal 4-5 times. Block the rear wheels and jack up the front end until the front wheels are off the ground. This will help you during the bleeding procedure.
2. Remove the upper nut attaching the flange to the hydro-booster.
   
3. Remove the (2) nuts attaching the master cylinder.
   
4. Remove the upper upper hydraulic line from the hydro-booster using the 18mm flare nut wrench.
   
5. Remove the lower hydraulic line from the hydro-booster. Access from the side and below the booster.
   
6. Remove the clamp on the return line, break the seal with a flat blade screwdriver, then pull hard.
   
7. Pull the hydraulic lines up and out of the way, then remove the lower nut attaching the flange to the booster.
   
8. Inside the cab locate the (4) 15mm nuts on the firewall that hold the booster in place.
9. Locate and remove the metal clip, pin, and washer attaching the booster pushrod to the brake pedal.
   
10. Remove the (4) hydro-booster mounting bolts. The top right bolt is accessed through a hole in the bracket.
    
11. Pull the hydraulic lines and bracket up and out of the way.
    
12. Remove the hydro-booster by pulling forward, up, and out.
    
13. Remove the spring retainer by prying up on one tab of the retainer, then pulling with your fingers, then remove the spring and master cylinder pushrod. Remove the rubber boot from the brake pedal pushrod end.
    
14. Reinstall the master cylinder pushrod, spring and retainer on the reman hydrobooster.
    
    
15. Reinstall the reman booster in the reverse order. Be carefull to not force the brake pedal rod in any direction while connecting it to the brake pedal. Napa instructions state this will void warranty.
16. Leave the 3/8" hydraulic return line disconnected until you complete the bleeding procedure.

Bleeding Procedure

1. Attach a 3/8" x 5ft hydraulic steering hose to the return connection on the side of the hydro-booster. Place the open end into a waste oil container.
2. Pull the #9 (20A) fuse from the fuse panel on the driver side of the dash. This will prevent the engine from starting while cranking and bleeding the hydraulics from the power steering pump.
3. Fill the power steering reservoir with fresh fluid.
4. Crank the engine for 10 seconds while pressing the brake pedal 5-10 times.
5. Check for fluid coming out of the bleed hose attached to the return line.
6. Refill the power steering reservoir and repeat until the fluid is coming out clear. I did this procedure three times.
7. Connect the return line using a new piece of the 3/8" hydraulic hose.
8. Replace the #9 fuse to enable the engine to start.
9. Check and refill the power steering fluid before starting the engine.
10. Run the engine for 10 seconds while truning the wheels from lock to lock. Do not hold the wheel against the stop.
11. Check and refill power steering fluid, then repeat step 10 two more times.
12. The power steering system is self bleeding and the reservoir should be checked frequently for the next few days until all the air has been expelled.

Hydro-Booster Function Test

1. Depress the brake pedal with the engine off.
2. Start the engine
3. Pedal should fall, then push back after the engine starts.

Brake Light Switch Adjustment

1. If your brake lights are on when the brakes are off, you will need to make a minor adjustment to the switch interface with the brake pedal.
2. Locate the brake switch mounting bracket and bolts under the dash.
3. Loosen the (2) bolts and with a helper at the rear, move the switch until the lights just go out with no pressure on the pedal.
4. Tighten the bolts and road test the vehicle.

Congratulations from one shade tree mechanic to another! You have just replaced your hydro-bootser and saved $300-400 labor.

 

[rotohead]

Thank you for this post. It's one of the last replacements I'm looking at in the future and a previous post was old and the pics disappeared from photobucket. I will print and save this to get me through a repair I hope I don't have to make. HA!!

 

[OakViewJeff]

I hope it can help you get the job done and tested. Mine started leaking on the raod, without my shop manual, and TDR helped me get it done right. Good luck with the reman unit, check it out for damaged studs or open ports that might have paint inside.