If your emergency brake isn't working properly, here's what you should do:
1. Check the brake shoes: Wear on the brake shoes is the most common cause of poor emergency brake performance. This requires removing the drums to inspect them. This is a job best left to a mechanic unless you have experience working on brakes. Low brake shoe material means replacement is needed.
2. Inspect the cables: Carefully inspect the emergency brake cables for any signs of fraying, rust, or damage. Look for kinks or areas where the cable might be binding. Again, replacement is typically needed if damaged. This also often requires some disassembly.
3. Check for binding: Make sure the emergency brake lever or pedal moves freely. If it feels stiff or binds, there could be an issue in the mechanism itself which needs professional attention.
4. Check the parking pawl: In some cases, there might be a problem with the parking pawl mechanism (the ratchet mechanism engaging the rear axles). This is a more involved repair requiring more mechanical skill.
In short: Do not attempt to manually adjust the emergency brake on a 2004 Chevy 3500. The system is not designed for that. If your emergency brake is not working correctly, take your truck to a qualified mechanic. Attempting to fix it yourself without the proper knowledge and tools could lead to further damage or injury. An ineffective emergency brake is a serious safety hazard.
