2018-2021 Ford F-150 3.0L Powerstroke Differential Parts

Differentials on the 2018-2021 F-150 3.0L Power Stroke

Every diesel F-150 carries its rear differential in a solid axle on leaf springs. A 4x4 adds a front differential that works with the independent double-wishbone front suspension. Gear ratios offered with the diesel include 3.31 and 3.55. For 2019, Lariat, King Ranch and Platinum buyers who ordered the Max Trailer Tow package got the 3.55 ratio with an electronic locking rear differential. Ford's launch material said the 2018 trucks got stronger axles. What Ford didn't publish is the diesel's ring-gear size, and F-150s of this era used both the 8.8-inch and the 9.75-inch rear axle depending on package.

What goes wrong

Water is the documented threat to these differentials. Ford's schedule treats any submersion as a reason for immediate service, and the signs that water got in are milky gear oil and bearing noise. Trucks that launch boats or cross flooded streets after a storm should get checked instead of waiting for the mileage interval. On the hardware side, 2021 trucks with the Trailer Tow Max Duty package and the 9.75-inch heavy-duty 3/4-float rear axle are covered by recall 23V896 for rear hub bolts that can fatigue and break. Clicking from the rear and damaged hub splines are the symptoms, and a VIN check tells you whether your truck is included.

Factory fill vs. the oils on this page

Ford's published spec is SAE 75W-85 full-synthetic hypoid gear oil on a 150,000-mile interval: 2.25 to 2.7 quarts in the rear and 1.7 to 1.9 quarts in a 4x4's front differential. The electronic locker, if you have one, takes no special additive per that same schedule. The oils listed in this collection are other viscosity grades, so check them against what your owner's manual allows for your axle. If you aren't sure, call us with your VIN and axle code before you pour.

What we carry

• Lucas Oil 10043 Heavy Duty 80W-90 Gear Oil for differential service.
• Royal Purple 01301 Max-Gear, a 75W-140 synthetic gear oil.

Pick a grade against your manual, then buy enough for the rear and, on a 4x4, the front. For the rest of the 3.0L catalog, see the Power Stroke hub.

Fitment notes

The 3.0L Power Stroke was an F-150 engine only, sold 2018 through 2021, and never offered in a Super Duty or a Regular Cab. 2018-2020 trucks are the 13th-generation F-150 and 2021 is the 14th. Whatever the year, identify the axle by its tag or the door-jamb axle code before you buy anything sized to it, and refill to the published capacity after any differential cover swap.

Frequently asked questions

How much gear oil does the rear differential hold?

The published capacity is 2.25 to 2.7 quarts of 75W-85 full-synthetic hypoid gear oil. A 4x4's front differential takes 1.7 to 1.9 quarts. Use the axle tag and your owner's manual to pin down the exact fill for your truck.

Which diesel F-150s got the electronic locking rear differential?

It's confirmed on 2019 Lariat, King Ranch and Platinum trucks with the Max Trailer Tow package, where it came with a 3.55 ratio. On any other year, check the window sticker or the door-jamb axle code. The published schedule calls for no special additive in the locker axle.

My truck sat in floodwater. Does the differential need service?

Yes. Ford's schedule calls for servicing the differentials and the transfer case right away after any submersion, no matter the mileage. Milky gear oil or new bearing noise means water got in.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.