Yukon Gear Jeep Wrangler JK Replacement Standard Carrier Case for Dana 30 Front / 3.73 & Up
If the front axle of a non-Rubicon Jeep Wrangler JK keeps eating spider gears, clunks when you engage 4WD, or came apart after a hard hit on the trail, the problem is often the open carrier case itself rather than the gears inside it. Yukon YC D2010999 is a new standard open carrier case built for the JK's front Dana 30, for gear ratios of 3.73 and numerically higher. It is the JK-specific case, not the older Dana 30 case used under the XJ, YJ and TJ, and that difference matters when you order the parts that go inside it.
The case is the iron housing that the ring gear bolts to. Its two bearing journals carry the carrier bearings, which ride in the axle housing saddles and set the ring gear's position against the pinion. Through the middle runs the cross pin, which carries the two spider gears that mesh with the side gears splined to the inner axle shafts. That is what lets the front tires turn at different speeds in a corner while 4WD is engaged. On the JK, the front Dana 30 is a reverse-rotation, short-pinion axle with a 7.2 in. ring gear, and Jeep put a Dana 44 up front on the Rubicon instead. Dana 30 cases are also split by gear ratio: deeper gears use a thicker ring gear that mounts at a different flange position, so this 3.73-and-up case will not accept a lower-ratio ring gear.
Pull the front cover, drain the oil and look at what came out. Rock the carrier and check the cross pin, its bore and the retaining bolt, then remove the carrier and inspect the bearing journals and ring gear bolt holes. If the case is clean and only the small gears are chipped, the cheaper fix is the Yukon JK Dana 30 spider gear kit. Confirm the ratio from the axle tag or by counting ring and pinion teeth before ordering, because this case is only for 3.73 and up. Our Dana 30 front axle problems and rebuild cost guide covers the other common failure points, and the carrier break explainer walks through why ratio decides which case you need.
Yukon catalogs this case for the Jeep Wrangler JK front Dana 30 with 3.73 and numerically higher ratios. That means 2007-2018 JK Wranglers and Unlimiteds without the Rubicon package; the Rubicon's front Dana 44 takes a different carrier. Yukon does not publish a vehicle-by-vehicle table for this part number, so check three things before you order: the axle is the JK reverse-rotation Dana 30, the ratio is 3.73 or deeper, and you are not trying to fit it to a TJ, XJ or YJ axle. Those older Jeeps use the standard Yukon Dana 30 open case YC D706008-X, and Yukon notes the JK spider gears do not fit that one. If you are unsure, send your year and VIN with the axle tag code and we will check it. More axle parts are in the hard parts collection.
This is a bare case, so plan the job as a carrier rebuild. You will move or replace the spider and side gears, press new carrier bearings onto the new journals, and bolt the ring gear on with clean threads and thread locker, torquing the bolts in a cross pattern to the factory figure. Re-gearing at the same time is common; a JK set like the Yukon Dana 30 JK reverse 4.56 gear set is a deep-ratio set that matches this case's carrier break. Because a new case can sit differently than the old one, recheck carrier bearing preload and backlash with a dial indicator and read the pattern with marking compound before closing it up. The Yukon YK D30-JK master overhaul kit supplies the Timken bearings, races, shims and seals for that job. Use a housing spreader to get the carrier in and out, spread only as far as the tool maker specifies, and refill with the 75W-90 gear oil Jeep calls for, plus friction modifier only if you install a clutch-type limited slip.
| Brand | Yukon Gear & Axle |
| Part number | YC D2010999 |
| Fits | Yukon Gear Jeep Wrangler JK Replacement Standard Carrier Case for Dana 30 Front / 3.73 & Up |
| Type | Differential Housings |
| 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.
No. The Rubicon JK has a Dana 44 front axle, which uses a different carrier. This case is for the Dana 30 front axle found under non-Rubicon 2007-2018 JK Wranglers.
Do not plan on it. Yukon separates the JK Dana 30 parts from the earlier Dana 30 parts and states the JK spider gears do not fit the standard Dana 30 case. Use the JK 27-spline spider gear kit in this case.
Not with those gears. This case is for 3.73 and numerically higher ratios only. If you are re-gearing to 4.10, 4.56, 4.88 or another deeper ratio at the same time, this is the case to use with the new gear set.
Spider and side gears, new carrier bearings, ring gear bolts in good condition, and a way to set preload and backlash. A JK master overhaul kit covers the bearings, races, shims and seals.
75W-90 gear oil. Fill to the bottom of the fill hole with the vehicle level. Add friction modifier only if a clutch-type limited slip is installed; an open case like this one does not need it.
