Yukon Gear Grizzly Locker For GM & Chrysler 11.5in w/ 30 Spline Axles
If your Silverado or Sierra 2500HD/3500HD, or your 2003-and-later Ram 2500/3500, keeps leaving one rear tire spinning on a wet boat ramp, a muddy job site or a snowy hill with a trailer behind it, the open carrier in its AAM 11.5 inch axle is the reason. The Yukon Grizzly Locker YGLGM11.5-30 replaces that carrier with a full mechanical locker built for the 11.5 inch ring gear and the factory 30-spline axle shafts. It needs no air lines, wiring or switches: it locks on its own when both wheels are driven and unlocks when the outside wheel has to run faster in a turn.
An open differential sends equal torque to both sides, so the axle can only push as hard as the tire with the least grip. The Grizzly uses a pair of driven clutch rings with face teeth instead of spider gears. Under power both rings stay engaged and the two axle shafts turn as one, so the tire with traction gets the torque. When you turn, the faster outside wheel ratchets its ring out of engagement and lets it overrun, then it drops back in once the speeds match. Yukon's description calls out a patented tooth profile with a larger radius at the base of the inner clutch teeth, which it rates at up to 350 percent stronger than back-cut designs, plus 8620 steel internals and US assembly. That matters in a heavy-duty truck where shock loads come from towing, hauling and off-road use rather than just horsepower.
The 11.5 AAM and the older GM 14-bolt 10.5 both have a 14-bolt cover, so do not order by cover shape. Check the axle tag or build sheet, and count the axle spline if the shafts have been swapped. Our GM 14-bolt vs AAM 11.5 comparison shows how to tell them apart, and the AAM 11.5 axle problems guide covers bearing and pinion wear that should be fixed during the same job. If you are weighing a selectable unit instead, read ELocker vs Grizzly Locker.
The YGLGM11.5-30 is for the rear AAM 11.5 inch axle with 30-spline shafts, all gear ratios. Published application charts list 2001-2019 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD, the 2003-2013 Ram 2500 and the 2003-2018 Ram 3500, and Yukon's own wording is that the chart is a reference only and the axle must be physically confirmed. Some later Ram 3500s and newer GM HD trucks use larger AAM axles, so send us your year and VIN if you are unsure. It does not fit the GM 14-bolt 10.5; that axle has its own Grizzly Locker for the 10.5 14-bolt. If you want the Eaton version of an automatic locker for the same axle, compare the Detroit Locker 250SL195A. More carriers are in our hard parts category.
These HD trucks use a full-floating rear axle, so the shafts slide out after the hub flange bolts come off; no C-clips are involved. Pull the carrier, move the ring gear to the Grizzly case with clean threads and new ring gear bolts, and install new carrier bearings rather than pressing the old ones off and back on. A Yukon master overhaul kit for 2010-and-earlier 11.5 axles or the 2011-and-later version covers bearings, races, shims and seals. Check backlash and the pattern after the carrier goes in, since a new case can move the ring gear. Fill with 75W-90 or 75W-140 gear oil; a locker of this type has no clutch packs and does not rely on friction modifier. Expect some clicking in tight turns and a slight push on single-rear-wheel trucks; that is normal behavior, not a defect. If you run oversized tires or heavy loads, consider 4340 chromoly 30-spline axle shafts as the next weak link.
| Brand | Yukon Gear & Axle |
| Part number | YGLGM11.5-30 |
| Fits | Yukon Gear Grizzly Locker For GM & Chrysler 11.5in w/ 30 Spline Axles |
| Type | Differentials |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Published charts for this locker stop at the 2019 model year. Newer GM HD trucks can use a different AAM axle, so send us your year and VIN or read the axle tag before ordering.
No. It accepts all ratios and your existing ring gear bolts to the new case. Many owners re-gear at the same time because the carrier is already out, but it is not required.
Automatic mechanical lockers can click or ratchet in tight, slow turns as the outside wheel overruns. On a heavy truck it is usually mild, and it does not mean anything is wrong.
Use a GL-5 75W-90 or 75W-140 gear oil. The Grizzly has no clutch packs, so friction modifier is not needed for the locker itself.
Carrier bearings and races at minimum, plus the pinion seal and cover gasket. If the pinion bearings are worn, a full master overhaul kit for your year of 11.5 is the better buy.
