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Nitro Gear & Axle Ring and Pinion Gear Kit; 3.90 Gear Ratio (05-10 Mustang GT)

Item 404786
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Market Price $294.39 You Save 13% ($38.40)
Our Price

$255.99 (kit)

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      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Performance Ring and Pinion Kit
      • Provide Optimal Performance for Your Mustang
      • 3.90 Gear Ratio
      • 8.80-Inch Ring Gear Diameter
      • Strong and Powerful 8620 Steel Construction
      • Professional Installation Recommended
      • 2-Year Warranty
      • Fits 2005-2010 Ford Mustang GT Models


      The Best Kit. When you’re looking for a ring and pinion kit for your 2005-2010 that will deliver performance and practicality, then you need the Nitro Gear & Axle Ring Gear and Pinion Kit – 3.90 Gears. Its heavy-duty construction provides lasting reliability, and the gear ratio ensures you’re going to be getting the performance you want at a fuel economy that you are happy with.

      8620 Gear Ratio. This gear and pinion have been constructed from superior 8620 steel. The heavy-duty material provides a superior resistance to wear and tear, keeping you in peak condition for years to come.

      Recommended Upgrade. If your Mustang’s gear ratio was not 3.90 before installing this kit, you will need to give its computer a tune-up to ensure speedometer accuracy. This can be done professionally, or with a handheld tuner, if you have it.

      Installation. This is a very advanced installation, requiring you to have advanced mechanical expertise, specialized tools, and at least 4 hours of install time to do it yourself. Professional installation is highly recommended here.

      2-Year Warranty. This ring and pinion kit is protected by Nitro’s 2-year warranty, defending against manufacturer defects from the date of purchase. See Nitro Gear’s full warranty for complete details.

      Application. This Nitro Gear & Axle Ring Gear and Pinon Kit – 3.90 Gears is designed to fit 2005-2010 Ford Mustang GT models. Please ensure the correct model and trim before purchase.



      Nitro Gear & Axle F8.8-390-NG

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Ring Gear
      • (1) Pinion

      Customer Reviews (4)

        Brand Image

        Reviews of Nitro Gear & Axle Drivetrain products have an average rating of 4.6 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • Bullitt - 08, 09
          • GT - 05, 06, 07, 08, 09, 10

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