Yukon Dana 30 Grizzly Locker - 27 Spline, 3.73 & Up Ratio
YGLD30-4-27
The Yukon Grizzly Locker for Dana 30 Axles is an automatic locking differential built to give your Jeep, rock crawler, or trail rig the traction it needs when the terrain gets tough. Instead of letting one tire spin while the other sits still, the Grizzly Locker automatically locks both axle shafts together under power to help keep you moving through rocks, mud, steep climbs, and uneven terrain. This version is designed for Dana 30 axles with 27-spline shafts and 3.73 or numerically higher gear ratios.
The Grizzly Locker uses a heavy-duty carrier and heat-treated 8620 steel internals with large engagement teeth designed to handle the shock loads of off-road driving. It operates mechanically without air compressors, wiring, or switches and allows differential action during turns when conditions permit. The carrier is also double-drilled for 3/8" and 7/16" ring gear bolts, giving builders more flexibility when assembling or upgrading a Dana 30 axle.
Includes:
- (1) Yukon Dana 30 Grizzly Locker Assembly
- Fully Assembled Internal Locking Mechanism
Specifications
| Manufacturer | Yukon Gear & Axle |
|---|---|
| Part Number | YGLD30-4-27 |
| Product Type | Automatic Mechanical Locker |
| Axle Platform | Dana Spicer 30 |
| Axle Spline Count | 27-Spline |
| Carrier Break | 3.73 and Numerically Higher Gear Ratios |
| Ring Gear Bolt Compatibility | 3/8" and 7/16" |
| Internal Material | Heat-Treated 8620 Alloy Steel |
| Locking Type | Automatic Mechanical |
| External Controls Required | No |
| Assembly | Fully Assembled Carrier |
| Country of Assembly | USA |
| Installation Type | Differential Carrier Replacement |
| Primary Application | Off-Road Traction Upgrade |
| Quantity | Sold Individually |
Fitment
Designed for Dana 30 differentials with 27-spline axle shafts and 3.73 or numerically higher gear ratios. Vehicle applications below are reference applications; confirm the installed axle configuration before ordering.
| Make | Model | Year Range | Axle Application |
|---|---|---|---|
| American Motors | Eagle | 1980–1988 | Dana 30 Front |
| Ford | Aerostar | 1986–1989 | Dana 30 Rear |
| Ford | Bronco | 1966–1971 | Dana 30 Front |
| International | Scout 800 / Scout II | 1967–1974 | Dana 30 Front |
| Jeep | Cherokee XJ | 1984–2001 | Dana 30 Front |
| Jeep | CJ5 | 1971–1983 | Dana 30 Front / Rear |
| Jeep | CJ6 | 1966–1975 | Dana 30 Front / Rear |
| Jeep | CJ7 | 1976–1986 | Dana 30 Front |
| Jeep | Comanche MJ | 1986–1992 | Dana 30 Front |
| Jeep | Commando | 1967–1973 | Dana 30 Front / Rear |
| Jeep | Grand Cherokee ZJ | 1993–1998 | Dana 30 Front |
| Jeep | Grand Wagoneer | 1984–1993 | Dana 30 Front |
| Jeep | Scrambler CJ8 | 1981–1986 | Dana 30 Front |
| Jeep | Wagoneer | 1971–1973 | Dana 30 Front |
| Jeep | Wrangler YJ / TJ / JK Non-Rubicon | 1987–2017 | Dana 30 Front |
| Volvo | 142 / 144 / 164 / 240 / 242 / 245 / 265 | 1970–1993 | Dana 30 Rear |
Fitment Notes:
- Requires Dana 30 differential with 27-spline axle shafts
- Designed for 3.73 and numerically higher gear ratios
- Double-drilled for 3/8" and 7/16" ring gear bolts
- Verify carrier compatibility, axle spline count, ring gear bolt size, and axle rotation before ordering
- Some vehicle models and years were available with multiple axle configurations
Installation Note: Replacing the differential carrier requires proper bearing preload, ring gear backlash, and gear contact pattern setup. Bearings, shims, and installation components should be selected for the specific axle.
FAQ
How does the Yukon Grizzly Locker work?
The Grizzly is an automatic mechanical locker that locks both axle shafts together when torque is applied. This helps maintain traction when one tire loses grip on rocks, mud, or uneven terrain. During turns, the mechanism can allow one wheel to overrun the other, depending on operating conditions.
What gear ratios will this Dana 30 Grizzly Locker fit?
This version is designed for Dana 30 axles with 3.73 and numerically higher gear ratios, including common 4.10, 4.56, 4.88, and 5.13 applications. Verify the specific gear set and carrier configuration before installation.
Will this locker fit my Jeep Wrangler TJ or JK?
It fits compatible Dana 30 applications using 27-spline axle shafts and the correct carrier configuration. Many Wrangler TJ and non-Rubicon JK front axles use the Dana 30 platform, but axle specifications should always be confirmed before ordering.
Does the Grizzly Locker require an air compressor or electrical switch?
No. The Grizzly Locker operates mechanically, so there are no air lines, compressors, electrical switches, or wiring to install. Engagement and disengagement happen automatically as the drivetrain loads and unloads.
Can I use this Grizzly Locker for rock crawling and trail riding?
Yes. Automatic lockers are a popular choice for rock crawlers and trail rigs because they provide traction without requiring the driver to manually engage a locker. Keep in mind that an automatic locker can change steering feel and handling, particularly in a front axle or on high-traction surfaces.
Does this locker work with both 3/8" and 7/16" ring gear bolts?
Yes. This Grizzly Locker carrier is double-drilled to accept both 3/8" and 7/16" ring gear bolts, allowing compatibility with different Dana 30 ring gear configurations.
Do I need an installation kit when replacing my differential carrier?
We recommend inspecting the existing bearings and using the correct carrier bearings, shims, and installation components for your axle. Proper backlash, bearing preload, and gear contact pattern are critical for reliable operation and long-term gear life.
