Assuming Drum Brakes (Most Likely):
1. Safety First: Engage the parking brake firmly. Block the front wheels to prevent the truck from rolling. Wear safety glasses.
2. Locate the Adjuster: You'll need to access the rear brake drum. This usually involves removing the wheel and tire. Once the drum is off, you'll see a star wheel adjuster. It's a small, star-shaped piece with notches that you can turn. This adjuster is what controls the distance between the brake shoes and the drum.
3. Adjust the Star Wheel: Using a screwdriver or a special star wheel adjuster tool (available at auto parts stores), carefully turn the star wheel. Turn it clockwise to tighten the brakes. Turn it a small amount at a time, then try to spin the drum. You want some resistance, but not too much. The drum should spin freely but with noticeable drag. The goal is to eliminate all the slack in the system. Too tight, and they'll drag and overheat; too loose, and they won't brake effectively.
4. Check for Evenness: It's crucial to ensure both brake shoes are adjusted equally. Uneven adjustment will lead to uneven braking and premature wear. Rotate the drum and feel for any difference in resistance.
5. Reassemble: Once you've achieved the correct adjustment, carefully reassemble the drum and wheel.
6. Test: After reassembling everything, test the brakes carefully. Start with gentle braking, gradually increasing pressure to ensure they're working correctly and smoothly.
If you have Rear Disc Brakes (Less Likely):
1986 Silverados with rear disc brakes will have a different adjustment procedure. They usually don't require manual adjustment like drum brakes do. The adjustment is typically automatic through the caliper pistons. However, there might be a parking brake cable adjustment if the parking brake isn't holding effectively. You'll likely find a cable adjuster near the caliper. A repair manual specific to your truck's configuration (disc brake option) will be needed.
Important Considerations:
* Repair Manual: A repair manual specific to your 1986 Chevy Silverado is highly recommended. This will provide diagrams and detailed instructions tailored to your particular truck.
* Worn Parts: If your brakes are extremely worn (thin brake shoes or excessively worn drums), adjustment alone won't fix the problem. You'll need to replace the worn parts.
* Professional Help: If you're uncomfortable working on your brakes, it's best to take your truck to a qualified mechanic. Brakes are a critical safety system.
This information is for guidance only. Always consult your vehicle's repair manual before attempting any brake work. Improper brake adjustment can be dangerous.
