When ever you change tire size from the original size to another there will be a direct effect on power and drivability. We have developed this chart to help you select the optimum gear ratio to put your performance back where you want it.
Using the chart below, first determine your original gear ratio and tire size and follow to the intersection that should be your approximate RPM at 65 MPH. Next find your new tire size and follow that across to the closest RPM to your original and that will be first choice.
If you are interested in a change that will give more power or better fuel mileage use the color coding as a guide.
Highway Driving, Good Fuel Economy
Daily Driver, Best Overall Performance
Most Power and Towing, Reduced Fuel Economy
This chart is based on 65 MPH and a gear ratio of 1:1, on a manual transmission in 4th gear. Please NOTE: If you have an automatic transmission your RPM will higher due to slippage in the transmission and the torque converter. With an overdrive transmission your RPM in overdrive will be 15% to 30% less than indicated.
The following parts require additional handling charges due to their large size or
weight: wheels, tires, full suspension lift kits, oversized bumpers, tire carriers, body tubs, hard tops
and cargo racks. The following parts do not qualify for free shipping: Oversized items and items
delivered by truck freight, as well as prior purchases and returns.
Jeep Parts & Jeep Accessories Take your Jeep to the next level with the parts found on our site. We are a leading Jeep accessories retailer, providing performance products for our customers. We work hard to give you the best information to turn your vehicle into a top-notch ride. Whether you are looking for 4wd suspension parts & accessories or want improved Jeep performance, we have the parts & Jeep accessories you need.
The terms Quadratec and Essentials are Registered Trademarks of Quadratec Incorporated, Registered in U.S. Patent and Trademark Office. All manufacturers names, numbers, symbols and descriptions are used for reference purposes only, and it is not implied that any part listed is the product of these manufacturers or approved by any of these manufacturers.
*Jeep, Wrangler, Rubicon, Renegade, CJ, Quadra-Trac and the Jeep Grille Design are registered trademarks of Chrysler LLC. Quadratec, Inc, has no affiliation with Chrysler LLC. Throughout this website and catalog the terms Jeep, Wrangler, MOPAR®, & Rubicon are used for identification purposes only. Geo is a registered trademark and Tracker is a registered trademark of the General Motors Company. Sidekick and Samurai are trademarks of Suzuki Motor Corporation. Amigo is a product of Isuzu Motors Limited. Chevrolet, the Chevrolet Emblem, S Series, GMC, GMC Truck, Chevy, Vortec and Sonoma are registered trademarks of the General Motors Company. Expedition, F-Series, F-150, F-250, F-350, Super Duty and Flare Side are registered trademarks of the Ford Motor Company. All other marks, names, and logos mentioned on this web site are the property of their respective owners.
Throughout this web site all the preceding marks & logos are used for identification purposes only. Quadratec has no affiliation with the Chrysler LLC, MOPAR®, General Motors Company, Ford Motor Company, Suzuki Motor Corporation or Isuzu Motors Limited. It is not implied that any part listed is a product of, or approved by Chrysler LLC, General Motors Company, Ford Motor Company, Suzuki Motor Corporation or Isuzu Motors Limited.
Quadratec, Inc. is sometimes mis-searched as Quadartec and Quadratech, we have no affiliation with either. 
* Free Shipping Special Offer Details
To qualify for FREE shipping the parts on an individual order must meet a combined total value of $75 or more. Customer must select Standard Shipping in the checkout and ship to an address in the contiguous 48 United States. Some parts require additional handling charges due to their large size or weight: including wheels, tires, full suspension lift kits, oversized bumpers, tire carriers, body tubs, hard tops, cargo racks, winches and hitches. Oversized items, items that are delivered by truck freight, prior purchases and returns do not qualify for free shipping.