SKU: YDGF9-31-AG | UPC: 883584260097
Yukon Gear Dura Grip Positraction Limited Slip Differential for Ford 9" 31 Spline Axles Aggressive Design Fits 1957-1988 Ford Models
The Yukon Dura Grip YDGF9-31-AG is a positraction limited slip differential designed for Ford 9-inch differentials with 31 spline axles. It fits a wide range of Ford vehicles from 1957 to 1988 including Mustangs Broncos F-Series trucks Fairlanes Rancheros and Econolines. This aggressive design provides smooth operation with strong traction for off-road street and track use delivering reliable power to both wheels.
Key Features
- Aggressive Clutch Pack: Composite clutches engage quickly for maximum grip in low traction conditions across dirt mud snow or pavement
- High Strength Nodular Case: Cast from durable nodular iron to withstand high torque and heavy abuse
- Forged 4320 Chromoly Spider Gears: Heat treated for exceptional strength and longevity under extreme loads
- Rebuildable Design: Serviceable clutches and components allow multiple rebuilds for extended service life
- Smooth Positraction Operation: Transfers power evenly without chatter for confident handling in varied terrains
Product Notes
- Direct replacement for open differentials or factory lockers in Ford 9-inch housings
- Requires proper break-in procedure with specific gear oil additive for optimal clutch performance
- Packaged in sturdy box dimensions 11.8 x 11.8 x 11.8 inches product weight 27.85 lbs shipping weight 30 lbs
Installation Notes
- Professional installation recommended.
- Confirm 31 spline axles and Ford 9-inch ring gear 9.0 to 9.75-inch diameter
- Uses factory hardware torque specs per Ford service manual includes clutch preload shims
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1957-1970 | Ford | Fairlane | 500 |
| 1966-1967 | Ford | Fairlane | 500XL |
| 1957-1969 | Ford | Fairlane | Base |
| 1960-1970 | Ford | Falcon | Base |
| 1962 | Ford | Falcon | Deluxe |
| 1963-1970 | Ford | Falcon | Futura |
| 1963-1965 | Ford | Falcon | Futura Sprint |
| 1959-1967 | Ford | Galaxie | Base |
| 1957-1974 | Ford | F-100 | Base |
| 1976-1978 | Ford | F-100 | Base |
| 1983 | Ford | F-100 | Base |
| 1975-1982 | Ford | F-100 | Custom |
| 1975-1978 | Ford | F-100 | Northland |
| 1975-1981 | Ford | F-100 | Ranger |
| 1978-1981 | Ford | F-100 | Ranger Lariat |
| 1975-1981 | Ford | F-100 | Ranger XLT |
| 1961 | Ford | Galaxie | Club Victoria |
| 1960 | Ford | Galaxie | Special |
| 1961 | Ford | Galaxie | Starliner |
| 1961 | Ford | Galaxie | Sunliner |
| 1961 | Ford | Galaxie | Town Victoria |
| 1968-1974 | Ford | Galaxie 500 | Base |
| 1968-1970 | Ford | Galaxie 500 | XL |
| 1972-1976 | Ford | Gran Torino | Base |
| 1964-1969 | Mercury | Comet | Base |
| 1971-1977 | Mercury | Comet | Base |
| 1967-1973 | Mercury | Cougar | Base |
| 1977-1979 | Mercury | Cougar | Base |
| 1969-1970 | Mercury | Cougar | Boss 302 |
| 1969-1970 | Mercury | Cougar | Boss 429 |
| 1977 | Mercury | Cougar | Brougham |
| 1966-1974 | Ford | Bronco | Base |
| 1975-1986 | Ford | Bronco | Custom |
| 1985-1986 | Ford | Bronco | Eddie Bauer |
| 1975 | Ford | Bronco | Northland |
| 1978 | Ford | Bronco | Northland |
| 1975 | Ford | Bronco | Ranger |
| 1978-1981 | Ford | Bronco | Ranger XLT |
| 1968-1969 | Ford | Bronco | Roadster |
| 1967-1979 | Ford | Ranchero | 500 |
| 1967 | Ford | Ranchero | 500 XL |
| 1957-1971 | Ford | Ranchero | Base |
| 1957-1958 | Ford | Ranchero | Custom |
| 1966 | Ford | Ranchero | Custom |
| 1968-1979 | Ford | Ranchero | GT |
| 1970-1979 | Ford | Ranchero | Squire |
| 1955-1979 | Ford | Thunderbird | Base |
| 1969-1970 | Ford | Mustang | Boss 429 |
| 1970-1973 | Ford | Mustang | Grande |
| 1970-1973 | Ford | Mustang | Mach 1 |
| 1965-1970 | Ford | Mustang | Shelby GT-350 |
| 1966 | Ford | Mustang | Shelby GT-350H |
| 1967-1970 | Ford | Mustang | Shelby GT-500 |
| 1968 | Ford | Mustang | Shelby GT-500KR |
| 1969-1970 | Mercury | Cougar | Cobra Jet |
| 1977 | Mercury | Cougar | Villager |
| 1967-1979 | Mercury | Cougar | XR-7 |
| 1975-1980 | Mercury | Grand Marquis | Base |
| 1979-1980 | Mercury | Grand Marquis | Colony Park |
| 1969-1974 | Ford | E-100 Econoline | Club Wagon |
| 1975-1983 | Ford | E-100 Econoline | Custom |
| 1975-1978 | Ford | E-100 Econoline | Northland |
| 1983 | Ford | E-100 Econoline | XL |
| 1979-1982 | Ford | E-150 Econoline | Base |
| 1984-1986 | Ford | E-150 Econoline | Base |
| 1969-1974 | Ford | E-200 Econoline | Club Wagon |
| 1970-1974 | Ford | E-200 Econoline | Custom Wagon |
| 1975-1980 | Ford | E-250 Econoline | Base |
| 1975-1980 | Ford | E-250 Econoline | Chateau |
| 1975-1980 | Ford | E-250 Econoline | Custom |
| 1975-1978 | Ford | E-250 Econoline | Northland |
| 1970-1976 | Ford | LTD | Brougham |
| 1975-1979 | Ford | LTD | Country Squire |
| 1975-1979 | Ford | LTD | Landau |
| 1970-1977 | Ford | Maverick | Base |
| 1975-1977 | Ford | Maverick | Grabber |
| 1965-1973 | Ford | Mustang | Base |
| 1969-1971 | Ford | Mustang | Boss 302 |
| 1971-1972 | Ford | Mustang | Boss 351 |
| 1973-1976 | Ford | Gran Torino | Brougham |
| 1974-1975 | Ford | Gran Torino | Elite |
| 1972-1975 | Ford | Gran Torino | Sport |
| 1972-1976 | Ford | Gran Torino | Squire |
| 1975-1979 | Ford | Granada | Base |
| 1978-1979 | Ford | Granada | ESS |
| 1975-1979 | Ford | Granada | Ghia |
| 1965-1979 | Ford | LTD | Base |
| 1975-1977 | Ford | Bronco | Sport |
| 1968-1973 | Ford | Bronco | Wagon |
| 1982-1983 | Ford | Bronco | XLS |
| 1984-1986 | Ford | Bronco | XLT |
| 1982-1983 | Ford | Bronco | XLT Lariat |
| 1969-1982 | Ford | E-100 Econoline | Base |
| 1975-1982 | Ford | E-100 Econoline | Chateau |
| 1975-1981 | Ford | F-150 | Ranger |
| 1978-1981 | Ford | F-150 | Ranger Lariat |
| 1975-1981 | Ford | F-150 | Ranger XLT |
| 1982-1987 | Ford | F-150 | XL |
| 1982-1983 | Ford | F-150 | XLS |
| 1977 | Ford | F-150 | XLT |
| 1983-1984 | Ford | F-150 | XLT |
| 1982 | Ford | F-150 | XLT Lariat |
| 1985-1987 | Ford | F-150 | XLT Lariat |
| 1978 | Ford | Thunderbird | Diamond Jubilee |
| 1979 | Ford | Thunderbird | Heritage |
| 1978-1979 | Ford | Thunderbird | Town Landau |
| 1958-1979 | Lincoln | Continental | Base |
| 1968-1971 | Lincoln | Mark III | Base |
| 1964-1965 | Mercury | Comet | 202 |
| 1964-1965 | Mercury | Comet | 404 |
| 1979-1982 | Ford | E-150 Econoline | Chateau |
| 1979-1983 | Ford | E-150 Econoline | Custom |
| 1987-1988 | Ford | E-150 Econoline | Custom |
| 1983-1988 | Ford | E-150 Econoline | XL |
| 1971-1972 | Ford | E-200 Econoline | Chateau Wagon |
| 1982-1983 | Ford | F-100 | XL |
| 1982-1983 | Ford | F-100 | XLS |
| 1977 | Ford | F-100 | XLT |
| 1982-1983 | Ford | F-100 | XLT Lariat |
| 1976-1978 | Ford | F-150 | Base |
| 1983-1986 | Ford | F-150 | Base |
| 1975-1982 | Ford | F-150 | Custom |
| 1987 | Ford | F-150 | Custom |
| 1975-1978 | Ford | F-150 | Northland |
Why Choose Yukon Gear?
- Over 40 years engineering driveline components for trucks SUVs and off-road vehicles
- Uses premium materials like chromoly steel and nodular iron for daily driver and race durability
- Precise tolerances ensure quiet operation and direct fit in OEM housings
Frequently Asked Questions
-
Q: Will this fit my 1969 Ford Mustang with Ford 9-inch rear?
A: Yes it fits 1965-1973 Mustang Base Boss 302 Boss 351 Boss 429 Mach 1 Shelby models with 31 spline axles confirm your axle spline count -
Q: What materials are used in the spider gears and case?
A: Forged 4320 chromoly spider gears and high strength nodular iron case built for high horsepower and torque applications -
Q: What warranty covers this Dura Grip?
A: Backed by Yukon Gear limited warranty rebuildable design extends usability contact manufacturer for details
Shipping & Handling
- Method: UPS Ground or FedEx
- Availability: In stock - ships same or next business day
- Packaging: Secure foam protected box 11.8 x 11.8 x 11.8 inches
- Weight: 27.85 lbs product 30 lbs shipping
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Yukon Gear & Axle provides the highest quality aftermarket drivetrain parts in the industry. Yukon products are produced using superior materials and built to tolerances that exceed OE specifications. We do drivetrain right! Yukon manufactures high performance ring & pinions, positractions, lockers, axle upgrades, rebuild kits, hubs, driveshafts, diff covers, and more. Proven at the King of the Hammers and the granite crags and outcrops of Moab, Yukon products are built for abuse so you can gear up and wheel with confidence. At Yukon Gear & Axle we make it our Mission to build quality parts that exceed expectation. It’s that simple! Our in-house engineering group utilizes state-of-the-art software to design product that’s then manufactured in partnership by some of the world’s foremost leaders in OEM manufacturing. After rigorous testing and intense quality inspection, we’re proud to call it Yukon.
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