Yukon GM 8.5" & 8.6" Grizzly Locker - 30 Spline, 2.73 & Up
YUKYGLGM8.5-3-30
Built for GM 8.5" and 8.6" rear axle builds, this 30-spline Grizzly Locker is a serious upgrade for trucks and rigs that need real traction under load. Whether you're working with a 10-bolt truck axle, LS swap car, or trail rig running larger tires, this locker delivers true mechanical lockup—sending 100% of available torque to both axle shafts when it matters.
The upgraded tooth profile and larger internal engagement teeth increase strength and reduce the risk of failure compared to traditional designs. Built with 8620 internals and assembled in the USA, this locker is right at home in GM truck axles being pushed hard—whether that’s a street-driven 10-bolt, prerunner, or a dedicated off-road build.
Includes:
- (1) GM 8.5" and 8.6" Locking differential (30-spline)
- Fully assembled internal gear set
Specifications
- Fits GM 8.5" and 8.6" differentials
- 30 spline axle compatibility
- Gear Ratio Compatibility: 2.73 and numerically higher
- Automatic mechanical locking differential
- 100% torque transfer to both wheels under load
- 8620 steel internal components
- Patented gear design for increased strength and durability
- Larger internal teeth to resist shock load and breakage
- Assembled in the USA
- Differential Cover Bolts: 10
Fitment
| Make | Model | Year Range |
|---|---|---|
| Buick | Apollo | 1973–1975 |
| Buick | Electra | 1971–1989 |
| Buick | Rainier | 2004–2007 |
| Buick | Regal | 1973–1987 |
| Buick | Riviera | 1975–1978 |
| Buick | Skylark | 1970–1979 |
| Cadillac | Escalade | 1999–2013 |
| Chevrolet | Avalanche | 2007–2013 |
| Chevrolet | Avalanche 1500 | 2002–2006 |
| Chevrolet | Bel Air | 1970–1975 |
| Chevrolet | Blazer | 1987–1994 |
| Chevrolet | C10 | 1979–1986 |
| Chevrolet | C10 Suburban | 1979–1986 |
| Chevrolet | C1500 | 1988–1999 |
| Chevrolet | C1500 Suburban | 1992–1999 |
| Chevrolet | C2500 | 1989–2000 |
| Chevrolet | Camaro | 1970–1981 |
| Chevrolet | Caprice | 1970–1996 |
| Chevrolet | Chevelle | 1973 |
| Chevrolet | Colorado | 2004–2012 |
| Chevrolet | El Camino | 1971–1976 |
| Chevrolet | Express 1500 | 1996–2014 |
| Chevrolet | G10 | 1979–1995 |
| Chevrolet | G20 | 1975–1995 |
| Chevrolet | Impala | 1971–1996 |
| Chevrolet | K10 | 1977–1986 |
| Chevrolet | K10 Suburban | 1977–1986 |
| Chevrolet | K1500 | 1988–1999 |
| Chevrolet | K1500 Suburban | 1992–1999 |
| Chevrolet | K20 | 1977–1986 |
| Chevrolet | K20 Suburban | 1977–1986 |
| Chevrolet | K5 Blazer | 1977–1986 |
| Chevrolet | Malibu | 1978–1983 |
| Chevrolet | Monte Carlo | 1973–1978 |
| Chevrolet | Nova | 1970–1979 |
| Chevrolet | R10 | 1987 |
| Chevrolet | R10 Suburban | 1987–1988 |
| Chevrolet | R1500 Suburban | 1989–1991 |
| Chevrolet | S10 | 1994–2004 |
| Chevrolet | Silverado 1500 | 1999–2017 |
| Chevrolet | SSR | 2003–2006 |
| Chevrolet | Suburban 1500 | 2000–2014 |
| Chevrolet | Tahoe | 1995–2017 |
| Chevrolet | Trailblazer | 2002–2009 |
| Chevrolet | V10 | 1987 |
| Chevrolet | V10 Suburban | 1987–1988 |
| Chevrolet | V1500 Suburban | 1989–1991 |
| Chevrolet | V20 | 1987 |
| Chevrolet | V20 Suburban | 1987–1991 |
| GMC | C1500 | 1979–1999 |
| GMC | C1500 Suburban | 1979–1999 |
| GMC | C2500 | 1997–2000 |
| GMC | Canyon | 2004–2012 |
| GMC | Envoy | 2002–2009 |
| GMC | G1500 | 1979–1995 |
| GMC | G25 | 1978 |
| GMC | G2500 | 1979–1995 |
| GMC | K15 | 1977–1978 |
| GMC | K15 Suburban | 1977–1978 |
| GMC | K1500 | 1979–1999 |
| GMC | K1500 Suburban | 1979–1999 |
| GMC | K25 | 1977–1978 |
| GMC | K25 Suburban | 1977–1978 |
| GMC | K2500 | 1979–1986 |
| GMC | K2500 Suburban | 1979–1986 |
| GMC | R1500 | 1987 |
| GMC | R1500 Suburban | 1987–1991 |
| GMC | Savana 1500 | 1996–2014 |
| GMC | Savana 2500 | 1996–1998 |
| GMC | Sierra 1500 | 1999–2017 |
| GMC | Sonoma | 1994–2004 |
| GMC | Typhoon | 1992–1993 |
| GMC | V1500 | 1987 |
| GMC | V1500 Suburban | 1987–1991 |
| GMC | V2500 | 1987 |
| GMC | V2500 Suburban | 1987–1991 |
| GMC | Yukon | 1992–2013 |
| GMC | Yukon XL 1500 | 2000–2014 |
| Hummer | H3 | 2006–2010 |
| Isuzu | Ascender | 2003–2008 |
| Oldsmobile | Cutlass | 1970–1977 |
| Oldsmobile | Cutlass Supreme | 1985–1987 |
| Oldsmobile | Omega | 1973–1979 |
| Pontiac | Bonneville | 1970–1986 |
| Pontiac | Catalina | 1970–1981 |
| Pontiac | Firebird | 1970–1981 |
| Pontiac | Grand Prix | 1971–1987 |
| Pontiac | GTO | 1970–1973 |
| Pontiac | LeMans | 1971–1981 |
| Pontiac | Ventura | 1976–1977 |
| Saab | 9-7x | 2005–2009 |
- Compatible with gear ratios 2.73 and up only
- Not compatible with lower (numerically higher) carrier breaks outside specified range
Tech Insight
Mechanical lockers like the Grizzly provide maximum traction by locking both axle shafts together under power. This ensures both tires receive equal torque, making it ideal for off-road and high-load applications where traction loss is common.
Unlike selectable lockers, automatic lockers engage and disengage based on load and wheel speed differences. Proper installation and setup are critical to ensure smooth operation, reduced noise, and long-term durability under aggressive driving conditions.
