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Richmond Gear 6903611 Ring and Pinion Set 3.70:1 Ratio Ford 9 Inch

(Ford F-150 1975-86, Mustang 1965-73, Bronco 1966-86, Thunderbird 1955-79, Maverick 1970-77, Galaxie 500 1962-74, F-100 1975-83 + 23 more models)

Part of: Richmond Gear Excel Differential Ring and Pinion Set

Other options in this family: Richmond Gear F9411 Richmond Gear 4900391 Richmond Gear 12BC373T Richmond Gear 6903041 Richmond Gear 7900601

Manufacturer

Picture for manufacturer Richmond Gear

Part Number

6903611
5 reviews
Sale Price

$384.20

4 left at this price

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Usually delivered within 2 days

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Product Details

The Richmond Gear 6903611 Ring and Pinion Set delivers professional-quality performance for Ford 9-inch differentials. This precision gear set features a 3.70:1 ratio with 37 ring gear teeth and 10 pinion gear teeth, making it ideal for street performance applications where balanced acceleration and cruising efficiency are required.

Key Specifications:

  • 3.70:1 gear ratio for Ford 9-inch differentials
  • 28-spline pinion with standard rotation
  • 9.000-inch ring gear diameter with 10-bolt pattern
  • 1.313-inch pinion shaft diameter
  • 37 ring gear teeth / 10 pinion gear teeth

What's Included:

  • Matched ring and pinion gear set
  • Installation specifications marked on gears

Richmond Gear is the leading manufacturer of professional-quality, high-performance ring and pinion sets, with superior quality resulting from years of racing development and state-of-the-art manufacturing methods. Each gear set is precision-matched and factory-tested to ensure proper tooth contact and long service life. Installation requires a professional-grade setup with proper shims, bearings, and seals (sold separately).

Important Notes:

  • Installation kit, bearings, seals, and crush sleeve not included
  • Professional installation strongly recommended
  • Requires proper setup with pinion depth gauge and backlash measurement
  • Each gear set is factory-matched and should not be mixed with other gears

Products specifications

Fits

Ford F-150 1975-86, Mustang 1965-73, Bronco 1966-86, Thunderbird 1955-79, Maverick 1970-77, Galaxie 500 1962-74, F-100 1975-83, Fairlane 1957-70, Ranchero 1957-79, Torino 1968-76, Galaxie 1959-67, Gran Torino 1972-76 + 18 more models

Calculator

Gear Ratio Calculator

Cover Bolts

10

Installation Kit Included

No

Pinion Gear Teeth

10

Pinion Shaft Diameter (in)

1.313 in.

Pinion Spline Count

28

Quantity

Sold as a set.

Ring and Pinion Ratio

3.70:1

Ring Gear Bolts

10

Ring Gear Diameter (in)

9.000 in.

Ring Gear Rotation

Standard

Ring Gear Teeth

37

Tool

Transmission Lookup

Ring Gear Bolt Quantity

10

Ring Gear Diameter

9

Ring and Pinion Gear Ratio

3.70

Differential Case Design Type

Ford 9

Cover Bolt Quantity

Dropout

Ring Gear Tooth Quantity

37

Pinion Shaft Diameter

1.313

Ring Gear Material

8620 Steel

Pinion Gear Tooth Quantity

10

Prop 65

WARNING: Cancer - www.p65warnings.ca.gov

Position

Rear

Checkout was fast and easy, can't wait to see the audi tail lights!

Quick and dirty- just the way I like it.

So far, so good.

Had the cheapest parts I could find, shipped within 2 days. Very reasonable shipping rates.

I ordered some floor mats for a Prius. Autoplicity was very competitive in their pricing. Not only that, they shipped quickly and had great feedback during and after I ordered. I would purchase from them again!

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