However, you *can* get an *indication* of potential problems without removal:
* Visual Inspection: Look for obvious signs of wear like deep grooves, scoring, or excessive rust. Check for cracks or damage. Look at the brake shoes for wear as well; significantly worn shoes suggest drum wear.
* Measuring Drum Thickness: While you can't measure the diameter easily, you *might* be able to get a rough measurement of the *thickness* of the drum using a large caliper or ruler. This is less accurate but could help. Access will still be limited. You’ll be feeling for the drum's surface through any access holes. This is not a reliable method for determining if the drums need replacing.
Why you MUST remove the drums for accurate measurement:
To determine if your brake drums need replacing, you need to know their diameter and/or thickness. The service manual for your 1992 Ford Ranger will specify the minimum acceptable thickness. Exceeding the minimum thickness means the drum is worn and needs replacement to ensure safe braking. This measurement must be taken with the drum removed and properly measured with a caliper.
In short: While you can make a visual assessment, obtaining an accurate measurement requires removing the brake drums. This is a simple job if you have basic mechanical skills, but if you're not comfortable doing it yourself, take your vehicle to a mechanic for inspection and service.
