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Richmond Ring Gear and Pinion Kit - 4.56 Gears (99-04 GT)

Market Price $267.21 You Save 9% ($24.29)
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$242.92

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  • Item 66500G99
  • MPN# 66500G99

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Ship to: Ashburn - 20149
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    Features & Details

    • Exceptional Quality
    • Handle Extreme Torque Applications
    • First-Run, Never Recycled Materials
    • 4.56 Gear Ratio
    • 8.8" Ring Gear Diameter
    • 2-Year / 100,000 Mile Warranty
    • Fits 1999-2004 GT Mustangs
    Enhanced Performance. If your New Edge Mustang has some serious torque and horsepower and you need something to help get you into the power band faster, look no further. Upgrading your 8.8" rear end with Richmond 4.56 Gears is great for 1999-2004 GT owners who want to lower their ETs and be the first to cross the finish line, crushing the competition.

    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. Due to this high numeric gear ratio, it will require a notched gear cross pin for proper installation.

    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 4.56 Ring and Pinion Gears will fit all 1999 to 2004 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. Note, a 28-spline S-Spring will be required for 28-spline Mustangs (sold separately) if you opt for the Trac-Lok rebuild.

    Fitment: 1999 2000 2001 2002 2003 2004 Details

    CA Residents: Warning: California's Proposition 65

    What's in the Box
    • (1) Ring Gear
    • (1) Pinion Gear
    Installation Info
    Tech Specs

    Approximate RPM for 1999-2004 GT


    Manual
    Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1 4753 6654        
    2 2812 3937 5062 6187    
    3 1856 2599 3341 4084 4826 5569
    4 1406 1969 2531 3094 3656 4219
    5 956 1339 1721 2104 2486 2869


    Automatic
    Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1 3994 5591        
    2 2180 3051 3923 4795 5667 6539
    3 1406 1969 2531 3094 3656 4219
    4 984 1378 1772 2166 2559 2953
    Will it fit my Mustang?

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    Customer Reviews (2) Write a Review

    Overall Rating 5

    out of 5 stars

    Installation Time:Less than 1 Hour

    • Performance Gain 4 4
    • Fit 4.5 4.5



    • 5/5

      Installation Time: Less than 1 Hour

      December 21, 2016

      Great product !

      Great gears. Could automatically tell the difference when driving. Will defenetely recommend to friends and family.

      CristianG

      Year: 2003 Submodel: GT

      Helpful (3)

    • 5/5

      December 21, 2016

      Thanks AM!

      Really work well and keep very good traction in the track

      JM

      Year: 2003 Submodel: Cobra

      Helpful (3)

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