Yukon Gear Steel Cover For Ford 8.8in

If the rear cover on your Ford 8.8 is dented from a rock or hitch strike, rusted through at the bolt flange, or keeps weeping gear oil no matter how many times it gets resealed, this is the part you are looking for. The Yukon Gear and Axle YP C5-F8.8-S is a plain steel replacement cover for the standard 10-bolt Ford 8.8 inch rear axle, the housing found under F-150 pickups, V8 Mustangs, Explorers, 4.0L Rangers, Broncos and the Crown Victoria family. It is a direct bolt-on that uses the factory bolt pattern, so it goes back on with the same ten bolts that came off.

What the cover does on a Ford 8.8

On the 8.8 the carrier, ring gear and pinion are serviced through the rear of the housing, so the cover is the only thing between the gear set and the road. It holds the gear oil in the sump the ring gear runs through, keeps water and grit out, and on a C-clip axle it is the access door you open whenever the cross pin, C-clips, spider gears or Traction-Lok clutches need attention. A cover that has been pushed in can sit close enough to the ring gear to rub, and a flange that is warped or rusted thin will not hold a seal. Either way the gears end up running low on oil, which is how a minor leak turns into a whine and then a rebuild.

Symptoms that point to a bad cover

• Gear oil wetting the bottom of the housing, the cover face or the inside of the tires after a long drive.
• A visible dent or crease in the cover, especially after off-road use or backing into something.
• Heavy scale or pinholes along the bolt flange on trucks from salt states.
• A rising whine on the highway on a truck that has been leaking for a while. Low oil wears pinion bearings, one of the 8.8's best-known failure points, so check the level before blaming the gears.
• Clicking or a scraping sound that follows wheel speed after the cover has been hit, which can mean the cover is touching the ring gear.

How to confirm it is the cover and not a seal

Clean the housing with brake cleaner, drive a few miles and look again. Oil that starts at the cover seam or a rust hole is a cover job. Oil that starts at the pinion yoke is the pinion seal, and oil on the backing plates or inside the wheels is an axle seal or bearing. If the noise is the bigger worry, our guide on telling transmission noise from differential noise walks through the road test, and the Ford 8.8 rear axle problems and rebuild cost page covers what else commonly wears in this axle.

Fitment

This cover is made for the conventional 8.8 inch solid rear axle with a 10-bolt cover. That axle was used in Ford F-150s from 1983 on, Broncos through 1996, V8 Mustangs from 1986, solid-axle Explorers through 2001, 4.0L Rangers and the Panther platform cars. It does not fit the 2015-and-later Super 8.8, which uses a 12-bolt cover, and it is not a cover for the independent-rear 8.8 used in later Explorers, Expeditions and Mustang Cobras or for the reverse-rotation 8.8 front axle. Count your cover bolts before ordering. If you are unsure which 8.8 you have, send us the year and VIN or the axle tag code and we will confirm it. Other 8.8 parts are listed in our hard parts catalog.

Install notes

• Drain the axle before pulling the cover. Look at the old oil and the magnet for chunks or heavy glitter, which tell you whether the inside needs work while it is open.
• Scrape every trace of old sealant off the housing face and clean both surfaces with solvent. A dirty or oily flange is the most common reason a new cover leaks.
• Seal it with a bead of RTV gear-oil-rated silicone run inside the bolt holes, or a reusable cover gasket. Tighten the ten bolts evenly in a crisscross pattern so the steel flange pulls down flat.
• Refill through the fill plug on the housing until oil just reaches the bottom of the hole. The 8.8 takes 75W-140 or 75W-85 gear oil depending on the vehicle; check your owner's manual. A Traction-Lok limited slip also needs the friction modifier Ford specifies.
• If the cover came off because of chatter or noise, this is the time to install a Traction-Lok clutch kit or, for a worn pinion bearing, a Ford 8.8 master bearing kit with Timken bearings, rather than buttoning it back up and opening it again later.

A steel cover is the stock-style choice: light, inexpensive and correct for daily drivers and towing rigs. If yours took a hit off-road, a heavier cast cover is worth considering, but for replacing a rusted or bent original this restores a sealed, factory-shaped housing. If the carrier bearings are noisy as well, the Yukon carrier installation kit for the 8.8 supplies the bearings and shims for that side of the job.

Will this cover fit my 2015 or newer F-150?

No. Starting in 2015 Ford used the Super 8.8, which has a 12-bolt cover. This Yukon cover has the 10-bolt pattern of the earlier 8.8 solid rear axle.

Do I need a gasket or sealant?

Yes. Use a gear-oil-rated RTV silicone or a reusable 8.8 cover gasket. Clean the housing face completely first, since leftover sealant or oil is the usual cause of a leak.

How much gear oil does it take after I swap the cover?

Fill through the housing fill plug until the oil reaches the bottom edge of the hole. Capacity varies by vehicle, so filling to the plug is the reliable method. Use 75W-140 or 75W-85 as your owner's manual specifies, plus friction modifier on a Traction-Lok axle.

My rear end whines. Will a new cover fix it?

Only if the whine came from running low on oil through a leaking cover and the gears and bearings are still healthy. A whine that stays after the oil is topped up usually means pinion bearing or gear wear, which needs a bearing kit or setup work.

Does it fit an Explorer with independent rear suspension?

No. The IRS 8.8 used in 2002 and later Explorers and other SUVs has a different housing. This cover is for the solid-axle 8.8 only.