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Richmond Ring Gear and Pinion Kit - 3.73 Gears (86-93 GT)

Market Price $258.51 You Save 9% ($23.50)
Our Price

$235.01

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  • Item 66501G87
  • MPN# 66501G87

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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 1986-1993 GT, 5.0 LX and SVT Cobra
Get Going. Looking to have some fun in your Foxbody but don't want to totally destroy your MPGs? Upgrade your rear end with a set of Richmond 3.73 Gears in your 1986-1993 5.0L and enjoy an improvement in your acceleration from a stop. These steeper gears are a great investment that'll allow your V8 Pony to get into 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 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 1986 to 1993 V8 Ford 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: 1987 1988 1989 1990 1991 1992 1993 Details

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

Approximate RPM for 1986-1993 GT


Manual
Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
1 3876 5427 6977      
2 2289 3205 4120 5036 5951 6867
3 1100% 2142 2754 3366 3978 4590
4 1150 1610 2070 2531 2991 3451
5 771 1079 1387 1695 2004 2312


Automatic
Gear @25 MPH @35 MPH @45 MPH @55 MPH @65 MPH @75 MPH
1 2761 3865 4969 6073    
2 1687 2362 3037 3712 4386 5061
3 1150 1610 2070 2531 2991 3451
4 767 1074 1380 1687 1994 2301
Will it fit my Mustang?
  • Foxbody - 87, 88, 89, 90, 91, 92, 93

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Customer Reviews (1) Write a Review

Overall Rating 4.0

out of 5 stars

  • Performance Gain 5 5
  • Fit 5 5



  • 4/5

    April 01, 2017

    5.0

    I've had these on 3 of my mustangs love 373 gear ratio

    91lxvallejo

    Year: 1991 Submodel: LX

    Helpful (0)

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