Yukon Gear Hardcore Diff Cover for Dana 30/Super 30

If the stamped steel cover on your Dana 30 front axle is dented into the ring gear, weeping gear oil around the edge, or has already been cracked open on a rock, this is the armored replacement. Yukon YHCC-D30 is a thick-walled Hardcore differential cover cast from high strength nodular iron, finished in black powder coat with a stainless steel accent plate and stainless cover bolts. It bolts onto standard and reverse rotation Dana 30 housings, the front axle found under many Jeep Cherokee, Wrangler and Grand Cherokee builds.

What the diff cover does on a Dana 30

On a Dana 30 the ring gear, carrier and spider gears sit behind a bolt-on cover at the back of the center section. That cover holds the gear oil in, and on a front axle it is also the lowest, most exposed part of the housing, hanging right where a rock or a ledge finds it. The factory stamped cover is thin. When it caves in it can touch the ring gear or the bolts of a locker, and when it splits the axle loses its oil and the gears and bearings follow. Yukon's nodular iron cover is built thick so it takes the hit instead, and the bolt-on casting also stiffens the open back of the housing, which Yukon says reduces deflection of the carrier under high torque. Its inner surfaces are contoured to move oil around faster for cooling, and a magnetic drain plug catches fine metal so you can see wear before it becomes a failure.

Symptoms that call for a new Dana 30 cover

• A cover pushed in far enough to scrape or knock against the ring gear when the axle turns.
• Gear oil seeping from the cover edge or a crack, with a wet, dirty lower housing.
• A whine or growl that started after a trail hit, from gears that have run low on oil.
• A locker or 4.56/4.88 gear set going in and you want to protect the new parts before the first trip.
• A drain or fill plug hole that has been stripped or patched.

How to confirm it before you buy

Look at the cover from below with a light. Any dent deeper than the ring gear clearance is a problem, so pull it, drain the oil and check the ring gear teeth and the carrier for contact marks. Fine glitter in the oil is normal wear; chunks mean the gears or bearings need attention, and our Dana 30 front axle problems and rebuild cost guide covers what to look for. If the bearings are noisy, pair the cover with a Dana 30 front master overhaul kit so the axle is opened only once.

Fitment

Yukon describes YHCC-D30 as a Dana 30 cover that fits both standard rotation and reverse rotation differentials, and the product title also names the Super 30. Yukon publishes no vehicle table for it, so check your axle before you order: the Dana 30 has a roughly 7.1 inch ring gear and a 10-bolt cover, used on the front of the 1984-2001 Jeep Cherokee XJ, Wrangler YJ, 1997-2006 Wrangler TJ, 1993-2005 Grand Cherokee ZJ and WJ, and the CJ, plus 1966-1971 Bronco and early Scout applications. The JL Wrangler front Dana 30 uses its own cover design, and the independent front axle in the Liberty is a different housing, so neither is a match. The quickest check is to count the cover bolts and compare the shape of your old cover or gasket with this one. If you are unsure, send us your year and VIN. More parts for this axle are under differential and driveline hard parts.

Install notes

• Drain the axle, remove the old cover and scrape both faces clean of old gasket or sealant. Clean the face with brake cleaner so the new seal sticks.
• Use a thin, even bead of gear-oil-resistant RTV or a quality gasket, never both stacked. Our guide on differential cover gasket vs RTV explains the trade-offs.
• Snug the bolts in a crisscross pattern, then torque evenly so the cover pulls down flat.
• Fill with 75W-90 gear oil to the bottom of the fill hole; check the fill height on a level surface.
• If the gears are being replaced at the same time, a Dana 30 4.88 ring and pinion for the TJ and the Dana 30 front master bearing kit cover the rest of the job.

Will this cover fit a JL Wrangler Dana 30?

No. Yukon makes a separate Hardcore cover for the JL front Dana 30 (YHCC-D30JL). YHCC-D30 is for the earlier 10-bolt Dana 30 cover pattern.

Does it work on a reverse rotation (high pinion) Dana 30?

Yes. Yukon states the cover fits both standard and reverse rotation Dana 30 differentials.

Will it clear a locker or a deeper ring gear?

Yukon designs Hardcore covers to protect lockers and gears, but clearance depends on the carrier. Before final torque, turn the axle by hand with the cover snugged to make sure nothing touches.

What comes with it?

Yukon lists the nodular iron cover with a stainless accent plate, stainless cover bolts and a magnetic drain plug. Gear oil and gasket or RTV are separate.

What gear oil should I use after installing it?

75W-90 gear oil, filled to the bottom of the fill hole. Use a limited-slip additive only if your carrier is a clutch-type limited slip.