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EXCEL from Richmond Ring and Pinion Gear Kit; 3.90 Gear Ratio (05-09 Mustang GT, GT500)Find parts that fit my vehicle

Item 21527G05
EXCEL from Richmond Ring and Pinion Gear Kit; 3.90 Gear Ratio (05-09 Mustang GT, GT500)
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$215.09
93 Reviews
On Sale

-10% $215.09 Was $238.99

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      Product Information

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

      Features & Specs

      • Superior Quality
      • 3.90:1 Gear Ratio
      • 8.8" Ring Gear Diameter
      • For Street or Track Use
      • Made in the USA
      • Fits 2005-2009 GT, Bullitt and Shelby GT500 Mustangs

      Description

      Improve Off The Line Acceleration. If you are still running the low ratio gears your V8 Mustang originally came with from the factory, you are probably finding it hard to get your pony up and moving. This is because most 2005-2009 Mustangs were equipped with 3.31 or 3.55 gears, which work very well for the fuel conscious daily commuter, but not for the spirited driver who wants jack rabbit like acceleration. By upgrading to a set of higher ratio 3.90 Richmond Excel Gears your Mustang will enter into its power band sooner which will help to improve low end torque and give you the quick off the line acceleration you're craving.

      Superior Quality. Richmond proudly manufactures their Ring and Pinion Gear Sets right here in the USA. Using state-of-the-art manufacturing processes and extensive quality control testing, Richmond produces a superior quality Ring and Pinion Gear Set at an excellent price. Richmond is so confident in the quality of their products that they back them with a 6 month, 50,000 mile no-nonsense warranty.

      Recommended Upgrade. Please note that when changing the gear ratio of your Mustangs rear differential that the calibration of your speedometer will no longer be correct and will display the wrong speed. However, you can easily fix this annoying issue with a Ford Racing Speedometer Recalibration Tool (sold separately).

      Application. This 3.90 ratio Richmond Excel Ring and Pinion Gear set will fit all 2005 to 2009 V8 Mustangs equipped with an 8.8" solid axle rear end, including the GT, Bullitt and Shelby GT500 models. A master bearing kit is recommended by most installers, especially on high mileage vehicles, see drop down option above.

      Technical Note. Installation costs will vary, but a good rule of thumb is between $250 and $300. Be sure to work with a reliable shop that you trust for installations. You can also save money on your installation labor by having your Trac-Lok rebuilt at the same time as your gears are installed, see drop down option above.

      Fitment:

      Details

      EXCEL from Richmond F88389

      CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Ring gear
      • (1) Pinion gear

      4.0

      Customer Reviews (93)

      Questions & Answers

      No questions about this product yet. Ask the First Question

      Will It Fit My Mustang

      • Bullitt - 08, 09
      • GT - 05, 06, 07, 08, 09
      • GT500 - 07, 08, 09

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