Tools You'll Need:
* Brake fluid: Use DOT 3 brake fluid, and *only* DOT 3. Using the wrong type can damage your system.
* Bleeding wrench: A wrench that fits your bleeder valve perfectly (typically 8mm or 10mm). A line wrench or a flare nut wrench will help prevent rounding the bleeder screw.
* Clear tubing: Long enough to reach a container to catch the fluid.
* Container: To collect the old brake fluid.
* Socket wrench: To remove the brake fluid reservoir cap.
* Gloves: Brake fluid is corrosive.
* Shop rags: For cleaning up spills.
* Helper: Crucial for efficient bleeding.
Procedure:
1. Locate the Bleeder Valves: These are typically located on the caliper at each wheel (front and rear). They're small nipples, usually on the top or inside of the caliper.
2. Check Brake Fluid Level: Ensure the master cylinder reservoir is full of fresh DOT 3 brake fluid. Don't let it get low during the bleeding process.
3. Bleeding Order: The generally accepted order is:
* Rear passenger side
* Rear driver side
* Front passenger side
* Front driver side
This order is based on distance from the master cylinder, starting furthest and working closest. This helps push air out more effectively. Some mechanics will suggest a diagonal pattern (rear passenger, front driver, rear driver, front passenger). Either is fine. The key is to start furthest from the master cylinder.
4. Attach the Tubing: Attach one end of the clear tubing to the bleeder valve and the other end to your collection container. Make sure the tubing is secure to prevent spills.
5. Open the Bleeder Valve (Slightly): Have your helper slowly pump the brake pedal several times and then hold it down. While the pedal is held down, slightly open the bleeder valve with your wrench. You should see brake fluid flowing through the tubing. The flow will likely be somewhat intermittent.
6. Close the Bleeder Valve: Close the bleeder valve before your helper releases the brake pedal. Repeat steps 5 and 6 several times until no more air bubbles are visible in the fluid. Keep an eye on the brake fluid level in the master cylinder and top it off as needed.
7. Repeat for Each Wheel: Repeat steps 4-6 for each wheel, following the correct bleeding order.
8. Check for Firm Pedal: Once you've bled all four wheels, have your helper pump the brake pedal several times. The pedal should feel firm and consistent. If it's spongy, you might need to bleed the brakes again.
9. Check for Leaks: After bleeding, carefully inspect the brake lines, calipers, and wheel cylinders for any leaks.
Important Considerations:
* Vacuum Bleeder: If you have difficulty getting the air out, using a vacuum bleeder can make the process significantly easier. They're available at most auto parts stores.
* Power Brakes: If your truck has power brakes, the pedal will be much easier to pump.
* ABS: If your truck has anti-lock brakes (ABS), bleeding the system can be more complex and may require specialized tools. Consulting a repair manual or a professional mechanic is recommended in this case.
Safety Precautions:
* Wear safety glasses: Brake fluid can splash and cause eye irritation.
* Work in a well-ventilated area: Brake fluid fumes can be harmful.
* Dispose of old brake fluid properly: Brake fluid is hazardous waste. Follow local regulations for disposal.
This process describes the basic procedure. For more detailed instructions specific to your 1986 Toyota 4x4, consult a repair manual for your specific model. If you're uncomfortable performing this task yourself, take your truck to a qualified mechanic. Properly bled brakes are essential for safe driving.
