Full 4F27E / FN4A-EL teardown kit: 14 frictions, 14 steels, 7 bonded pistons, brake band, filter, gaskets and seals for Focus and Mazda 3.
Many Focus and Mazda3 owners pay for a 4F27E rebuild, only to have it slip on the 2-3 shift or engage late into Drive a few months later. The cause is often the original bonded pistons. A typical soft-parts kit replaces the frictions and gaskets, but the factory pistons go back in with lips that have hardened from years of heat. This kit closes that gap. One box includes 14 friction plates, 14 steel plates, the overhaul gasket and seal set, a new brake band, a pan filter and a 7-piece bonded piston set. It fits the Ford 4F27E and the matching Mazda FN4A-EL, 1999 and up.
The 4F27E is a four-speed front-drive transaxle that Ford and Mazda developed together. Mazda calls it the FN4A-EL, and Ford later built a five-speed relative called the FNR5. Each clutch in the unit is applied by a bonded piston, which is a steel piston with the rubber seal molded directly onto it. When that rubber hardens or cracks, apply oil leaks past the seal and the clutch slips even with new friction plates. Second and fourth gears rely on the band, so a worn band or band servo shows up as a missing second or a flare when the transmission shifts into fourth. This kit replaces every one of those wear parts in a single teardown: each friction and steel plate, every piston seal, the band, the filter and the case and valve body gaskets.
Some 4F27E symptoms are caused by the valve body, not the clutches. TransGo lists wrong-gear starts, a missing or skipped second gear, neutral on a kickdown and TCC slip codes as faults caused by worn valve body bores. Start by checking the solenoids at the case connector. TransGo's chart lists 1 to 4 ohms for shift solenoids A, B and C, 10 to 26 ohms for D and E, and 2.3 to 7.4 ohms for the pressure control solenoid. If those check good and the fluid is burnt, the hard parts are worn. If you have a P0741, read our gear ratio code guide and remember that Transmission Digest traces most 4F27E converter slip codes to worn pump-stator bushings, not to a failed solenoid.
The listing covers the Ford Focus, Fiesta, EcoSport and Transit Connect, plus the Mazda 2, 3, 5, 6, Protege, Tribute, CX-3 and CX-7 with the 4F27E or FN4A-EL four-speed. The listed cross-references are K71900KP, K71900KPX, K71900KFX, DP2352, DP2483, 46500F, 133800 and XS4Z-7D034-AB. This kit does not fit the FNR5 five-speed. Check the tag on the case before you order, or send us your year and VIN. You can find more parts for this transmission on our 4F27E parts page.
If the solenoid resistance is out of spec, add the 4F27E solenoid block. If the valve body has worn bores, add the TransGo valve body repair kit on the same job.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It adds a 7-piece bonded piston set, a brake band and a filter to the 14 frictions, 14 steels and gasket and seal set. Most kits leave the old pistons, band and filter in place.
Yes. The FN4A-EL is Mazda's name for the same four-speed. The kit does not fit the FNR5 or FS5A-EL five-speed.
Not always. Drums, the pump and other hard parts can be reused if they measure good. Check the pump-stator bushings carefully because wear there causes converter slip codes.
MERCON V for Ford 4F27E units. For Mazda units, use the fluid named in the owner's manual or on the dipstick. Use the same fluid to soak the frictions.
It will if the band, servo or clutch seals are the cause. If the fluid is clean and the problem is wrong-gear starts or a skipped 2nd, check the valve body and solenoids first.
