Silverado replacement leaf spring 22-1221 is the lightest weight capacity spring that was used on the 2005 Silverado 1500. You can verify which spring you have by checking the number OEM number on original spring (Stamped on bottom of second stage). The 22-1221 is the most commonly used spring on the 2005 Silverado 1500's. Feel free to call us at 1-800-358-4751 if you have any questions.