Yukon Gear Dura Grip For Ford 10.25in & 10.5in

Yukon DuraGrip Limited-Slip Positraction for Ford Sterling 10.25 in. and 10.5 in. (YDGF10.25-35-1)

The YDGF10.25-35-1 Yukon DuraGrip is a clutch-pack limited-slip differential (positraction) engineered to fit the Ford Sterling 10.25 in. and 10.5 in. rear axle housing found in F-Series trucks, E-Series vans, and the Excursion from 1985 through 2019. Unlike an open differential, the YDGF10.25-35-1 uses composite clutch packs and forged 4320 chrome-moly spider gears to automatically transfer torque to the wheel with the most traction, improving traction on loose surfaces, snow, and mud without the aggressive engagement characteristics of a full mechanical locker. The nodular iron case is engineered for long service life, and the unit is fully rebuildable when clutch packs wear.

Features and Benefits

• Fits Ford Sterling 10.25 in. and 10.5 in. rear differentials with 35-spline full-float bolt-in axle shafts
• Compatible with all gear ratios
• Clutch-pack positraction design for smooth, progressive torque transfer
• High-strength nodular iron case resists cracking and distortion under load
• Internal spider gears forged from 4320 chrome-moly steel, cut for stronger gear teeth than cast alternatives
• Composite clutch packs for extended service life and reduced chatter
• Fully rebuildable; replacement clutch kits are available separately
• Assembled in the USA
• 12 cover bolts (full-float axle housing)
• 1-year limited warranty against manufacturing defects

Vehicle Fitment

Specifications

What's Included

• Yukon DuraGrip positraction carrier assembly (YDGF10.25-35-1), fully assembled, USA-built
• Composite clutch pack set (pre-installed)

Note: Carrier bearings, ring and pinion gears, shim kit, and LSD additive are sold separately. Yukon recommends high-grade non-synthetic GL-5 gear oil with two bottles of Yukon LSD additive (part OILADD).

Frequently Asked Questions

What is the difference between a Grizzly Locker and a DuraGrip?
The Yukon Grizzly Locker is a full mechanical locker that locks both wheels together 100% of the time while driving straight, automatically disengaging in turns. The YDGF10.25-35-1 DuraGrip is a clutch-pack limited-slip differential (positraction) that progressively transfers torque from the spinning wheel to the one with traction. The DuraGrip provides better daily drivability and reduced tire scrub on pavement, while the Grizzly Locker is the choice for maximum grip in extreme off-road use.

Will the YDGF10.25-35-1 work with my gear ratio?
Yes. The YDGF10.25-35-1 is compatible with all gear ratios in the Ford Sterling 10.25 in. and 10.5 in. differential housings.

Does the YDGF10.25-35-1 require a break-in period?
Yes. Yukon recommends an approximately 500-mile break-in driving period under varied conditions before any sustained high-load use. During break-in, avoid excessive wheel spin and severe shock loads to allow the composite clutch packs to seat properly.

What oil should I use with the YDGF10.25-35-1?
Yukon strongly recommends standard non-synthetic 80W-90 GL-5 gear oil with two bottles of Yukon LSD additive (part OILADD). Synthetic oil is not recommended and may cause chatter or aggressive engagement behavior.

Is this the same as the factory Ford Traction-Lok?
The YDGF10.25-35-1 DuraGrip is an aftermarket clutch-pack positraction unit designed to replace or upgrade the factory Ford Traction-Lok limited-slip. It uses improved 4320 chrome-moly spider gears and composite clutch packs for better long-term durability.

Can the YDGF10.25-35-1 be rebuilt when the clutches wear?
Yes. The YDGF10.25-35-1 is fully rebuildable. Replacement composite clutch kits are available separately from Yukon Gear.

What does the Magnuson-Moss Warranty Act mean for my purchase?
Under the Magnuson-Moss Warranty Act, installing this aftermarket part does not void your vehicle's factory warranty unless the manufacturer can demonstrate the part caused the specific failure. Yukon backs the YDGF10.25-35-1 with a 1-year limited warranty against manufacturing defects.

Does this fit F-150 trucks as well?
Select F-150 models from 2000-2013 equipped with the Sterling 10.25 in. rear axle (typically higher-trim and performance variants) are compatible with the YDGF10.25-35-1. Verify your F-150's rear axle code before ordering, as most F-150s use the 8.8 in. rear axle.

Installation Overview

1. Lift and safely support the rear of the vehicle; remove the rear wheels and brake drums or calipers.
2. Drain the differential fluid and remove the rear differential cover.
3. Remove the axle shafts (full-float: remove the axle shaft retaining bolts at the hub).
4. Remove the pinion shaft lock bolt and slide out the pinion shaft; remove the spider gears and side gears.
5. Mark and remove the carrier bearing caps; extract the OEM differential carrier.
6. Transfer carrier bearings from the old carrier to the YDGF10.25-35-1 DuraGrip using a bearing press.
7. Install the ring gear onto the DuraGrip carrier; torque ring gear bolts to spec with thread-locking compound.
8. Install the YDGF10.25-35-1 into the housing; reinstall bearing caps and adjust shims to achieve correct backlash and bearing preload.
9. Reinstall axle shafts and all retaining hardware.
10. Clean the differential cover surface, apply RTV or new gasket, reinstall the cover, and fill with non-synthetic 80W-90 GL-5 gear oil plus two bottles of LSD additive.
11. Reinstall wheels, lower the vehicle, and test drive to verify smooth, quiet operation.

California Proposition 65 Warning: This product can expose you to chemicals including arsenic, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.