10R140 Transmission Filter and 10qt Mercon ULV Service Kit

This is a complete fluid-and-filter service kit for the Ford 10R140 ten-speed automatic, the transmission behind the 6.7L Power Stroke in 2020-and-newer F-250, F-350, F-450 and F-550 Super Duty trucks. It pairs the correct internal filter (OE number FT221, Ford part LC3Z-7G186-A) with ten quarts of Mercon ULV (Motorcraft XT-12-QULV), the low-viscosity fluid the 10R140 is spec'd for.

A basic drain-and-fill on the 10R140 pulls roughly 8 quarts. A full filter service with the pan dropped takes more, which is why the kit ships with ten quarts so you finish the job in one shot without a second parts run. Use the extra to bring the level in after the truck is at operating temperature.

On the bench or on the lift the job is straightforward: drop the pan, pull the old filter, seat the new FT221, reseal the pan, then fill and set the level to the factory temperature window. The 10R140 is sensitive to fluid condition and level, so keeping fresh ULV in it is the cheapest maintenance you can do on a work truck.

Neglected or overheated fluid in these units shows up as harsh 1-2 shifts, torque-converter shudder under light throttle, and delayed engagement into drive or reverse. A fluid-and-filter interval on schedule is cheap insurance against a valve body or converter-clutch failure that costs many times more.