2004 Chevrolet Venture Brake Service (ONLINE REPAIR MANUALS)

Hard Pedal

• Internal vacuum leak.
• Faulty control valve.
• Broken or damaged hydraulic brake lines.
• Collapsed or damaged vacuum hose.
• Plugged or loose vacuum fitting.
• Bad stud welds on front or rear housing on power head.
• Faulty booster diaphragm.
• Restricted air filter element.
• Worn or distorted reaction plate or levers.
• Cracked or broken pow...

Aztek, Rendezvous & Vue

Removal

• Raise and support vehicle.
• Mark relationship of drum to hub.
• Remove and discard retaining clip.
• Remove brake drum. If brake drum does not come off easily, proceed as follows:
• Loosen parking brake cable.
• Remove backing plate access hole plug.
• Disengage self adjuster by inserting suitable flat-bladed tool through backing plate access hole.
• Loosen adjuster screw by inserting another flat-bladed tool through access hole .
• Install access hole plug.
• Apply small amount of penetrating oil around brake drum center hole.
• Remove brake drum.
• Disengage adjuster spring hook e...

Height Sensing Proportioning Valve

The height sensing proportioning valve must be adjusted whenever the valve and/or linkage is disassembled or removed for service. In addition, adjustment should be inspected if excessive front wheel lock-up is experienced with a lower than desired brake application rate when vehicle is at or near maximum GVWR.

• Raise and support vehicle, leave wheels on and allow axle to hang freely.
• Remove lever retaining nut and disconnect lever from valve shaft, Fig. .
• Rotate valve shaft to permit installation of correct adjustment gauge, Fig. , ensure D shaped hol...

General System

• Inspect components for damage or unusual wear. Replace as required.
• Inspect backing plate mounting bolts and ensure they are tight.
• Inspect wheel cylinders. Excessive fluid indicates cup leakage and need for wheel cylinder replacement. Slight amount of fluid is always present and is considered normal, acting as lubricant for cylinder pistons.
• Inspect adjuster screw operation. If satisfactory, lightly lubricate adjusting screw and washer with suitable brake lube. If operation is unsatisfactory, replace.
• Clean rust and dirt from shoe contact surfaces on backing plate using fi...

Certain general service procedures apply, regardless of whether the brakes are vacuum or hydraulically assisted. Only top quality, clean brake fluid should be used. More seals and valves are used with power brake systems than with ordinary brakes, so an inferior brake fluid will do much more damage. For the same reason, ensure all dirt is kept out of the system. Additionally, on models with hydraulic assist brakes, care must be taken not to mix the fluids of the booster hydraulic system and brake hydraulic system as the fluids are not compatible.

If the power unit fails, the brak...

Master Cylinder

• On models equipped with manual brake system,disconnect master cylinder pushrod from brake pedal.
• On all models, disconnect all wire con...