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Richmond Ring and Pinion Gear Kit; 3.73 Gear Ratio (05-09 Mustang GT)

Item 66501G05
AmericanMuscle no longer carries the Richmond Ring and Pinion Gear Kit; 3.73 Gear Ratio (05-09 Mustang GT). Please check out 2024-2026 Ford Mustang Drivetrain for an updated selection.
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    Product Information

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

    Features

    • Exceptional Quality
    • Handle Extreme Torque Applications
    • First-Run, Never Recycled Materials
    • 3.73 Gear Ratio
    • 8.8" Ring Gear Diameter
    • 2-Year / 100,000 Mile Warranty
    • Fits 2005-2009 GT Mustangs

    Description

    Get Going. If you want to improve your acceleration from a stop in your 2005-2009 GT Mustang, you'll want to invest in a steeper gear. This 3.73 Richmond Ring and Pinion would be a great option and allow your V8 Pony to get to the power band faster. One of the highest quality gears on the market, you can't go wrong with Richmond in your high performance Mustang.

    Superior Quality. Manufactured right in the United States, Richmond Gear uses only the highest standards to produce the highest quality gears in the industry. Inspected and scrutinized to deliver gears with acceptable tolerances, durability and fit, Richmond ensures only the best in machining, finishing and heat treating of their drivetrain components.

    Recommended Upgrade. When changing the gear ratio of your Mustang's rear differential, the calibration of your speedometer will no longer be accurate and will display the wrong speed. However, you can easily fix this annoying issue with a Tuner or Recalibration Tool (sold separately).

    Installation Notes. An Installation and Bearing Kit is highly recommended by most installers, especially on high mileage Mustangs. Please see ordering options above.

    Warranty. Richmond Gears is so confident in the high quality of their ring and pinions that they are backed by a 2-Year / 100,000 Mile No-Nonsense Warranty.

    Application. These Richmond 3.73 Ring and Pinion Gears will fit all 2005 to 2009 GT Mustangs equipped with an 8.8" rear end.

    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 your gears are installed. See ordering options above.

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

    Installation & What's in the Box

    Installation Info

    Installation Time

    (approx) a Day

    Difficulty Level:

    Mechanical expertise or professional installation required.

    Installation Guides

      No guide available for this part yet.

    What's in the Box

    • (1) Ring Gear
    • (1) Pinion Gear

    Tech Specs

    Approximate RPM for 2005-2009 GT


    Manual
    Gear@25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1388854436998   
    2230132214141506159816902
    3151821262733334039484555
    4115016102070253129913451
    578210951408172120342347


    Automatic
    Gear@25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1370451856667   
    226343688474157956849 
    3177124803189389746065314
    4115016102070253129913451
    581711431470179721232450
    4.9

    Customer Reviews (26)

    Questions & Answers

    No questions about this product yet. Ask the First Question