1. Identify the Rubbing Pulley: First, *carefully* inspect the lower pulleys on your Astro's engine. There are several pulleys driven by the serpentine belt; pinpoint *exactly* which one is rubbing against the control arm. Take pictures if possible.
2. Determine the Cause: The rubbing is likely due to one of these:
* Misaligned Pulley: The pulley itself might be slightly bent or out of alignment. This could be from a previous impact or just wear and tear over time.
* Worn Pulley: The pulley itself might be worn down, causing it to sit closer to the control arm.
* Worn or Damaged Bracket: The bracket that holds the pulley might be bent or broken, causing the pulley to be positioned incorrectly.
* Control Arm Issues: In rare cases, the control arm itself might be bent or out of alignment. This is less likely, but possible.
* Incorrect Belt Routing: An improperly routed serpentine belt can put extra tension on one or more pulleys, causing them to rub.
3. Troubleshooting and Repair:
* Visual Inspection: Carefully examine the pulley, its bracket, and the control arm for any obvious signs of damage, bending, or wear.
* Belt Tension: Check the serpentine belt tension. If it's too tight, it can pull the pulleys closer to the control arm. Consult your owner's manual for proper tension specifications. Use a belt tension gauge for accuracy.
* Pulley Alignment: If the pulley seems misaligned, try gently rotating it by hand. If it feels rough or binds, it may need to be replaced.
* Bracket Inspection: Look closely at the pulley bracket for cracks, bends, or rust. If damaged, it'll need repair or replacement.
* Control Arm Check (Less Likely): If you suspect a control arm issue, you'll need a professional inspection. A bent control arm is a serious problem and needs a proper alignment.
* Pulley Replacement: This is often the solution. Replacing the offending pulley is relatively straightforward if you're mechanically inclined. You'll need the correct replacement pulley for your Astro's engine.
4. Repair Steps (if replacing pulley):
* Disconnect the Battery: Always disconnect the negative battery terminal before working on any car's electrical system.
* Remove the Serpentine Belt: Consult your owner's manual or an online repair guide for the proper procedure. There are usually tools specifically designed for this.
* Remove the Pulley: Access to the pulley will vary depending on its location. You might need to remove other components to get to it. Expect bolts, possibly nuts, and maybe some stubborn rust or corrosion.
* Install the New Pulley: Make sure the new pulley is properly aligned and securely fastened.
* Reinstall the Serpentine Belt: Follow the correct routing diagram in your owner's manual.
* Reconnect the Battery: Reconnect the battery's negative terminal.
* Test Run: Start the engine and listen carefully for any unusual noises. Check the pulley for rubbing again.
Important Considerations:
* Safety First: Working on a vehicle can be dangerous. If you're not comfortable performing these repairs yourself, take your Astro to a qualified mechanic.
* Correct Parts: Make sure to use the correct replacement pulley for your specific Astro model and engine.
* Alignment: If the problem persists after replacing the pulley, a suspension alignment might be necessary.
Remember to consult your owner's manual and possibly online repair guides specific to your 2000 Chevy Astro van for detailed instructions and diagrams. The exact procedure will depend on the specific pulley causing the problem.
