The brake booster check valve on a 2002 Dodge Durango 4.7L is
integrated into the brake booster itself. It's not a separate, easily accessible component. To access it, you'd essentially have to remove or at least partially disassemble the brake booster. This is a more involved job requiring mechanical skills and specialized tools.
Therefore, there isn't a specific "location" you can point to like a standalone part. If you suspect a problem with the check valve (e.g., hard brake pedal, low vacuum), the whole brake booster assembly is usually the item that gets replaced rather than attempting to repair the internal check valve.
