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Richmond Ring Gear and Pinion Kit - 3.73 Gears (99-04 GT)

Market Price $258.51 You Save 9% ($23.50)
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  • Item 66501G99
  • MPN# 66501G99

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Ship to: ASHBURN - 20146
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    Features & Details

    • 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 1999-2004 GT Mustangs
    Better Acceleration. If you need to upgrade your 8.8" rear end gears, look no further than the Richmond 3.73 Gears. You'll be able to acceleration faster, leave the line on a dime and get into the power band quicker in your New Edge Pony. Being 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 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

    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 3888 5443 6998      
    2 2301 3221 4141 5061 5981 6902
    3 1518 2126 2733 3340 3948 4555
    4 1150 1610 2070 2531 2991 3451
    5 782 1095 1480 1721 2034 2347


    Automatic
    Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
    1 3267 4573 5880      
    2 1783 2496 3209 3922 4636 5349
    3 1150 1610 2070 2531 2991 3451
    4 805 1127 1449 1771 2093 2416
    Will it fit my Mustang?

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    Customer Reviews (1) Write a Review

    Overall Rating 5

    out of 5 stars

    Installation Time:Afternoon

    • Performance Gain 4 4
    • Fit 5 5



    • 5/5

      Installation Time: Afternoon

      December 26, 2016

      Great product!

      Didn't take long to install. Great product! Thanks AM!

      Ruck

      Year: 2001 Submodel: GT

      Helpful (4)

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