Master overhaul kit for the Ford 4R44E, 4R55E, 5R44E and 5R55E, 1997-2003, with the steel plates, frictions, gaskets and seals included.
A 1997-2003 Ranger, Explorer, Mountaineer or Mazda B-series that slips between gears, shifts late and soft, or has a pan full of black fluid is usually due for a complete overhaul. This ATP FM-43 master kit covers the whole small-case Ford family from those years: the four-speed 4R44E and 4R55E and the five-speed 5R44E and 5R55E. Its key advantage is that it includes the steel plates alongside the frictions, so a burnt unit can be rebuilt completely from one box.
Per Sonnax, Ford introduced the 4R44E in 1995 behind the 2.3L and 3.0L, strengthened it into the 4R55E for the 4.0L in 1996, and made it a five-speed in 1997 by applying the front servo for an extra overdriven ratio. That history matters for a rebuild kit, because the clutch packs and the circuits sealed by the gasket set are largely common across all four versions. FM-43 includes:
Everything ships vacuum packed to boards, so the frictions arrive flat. The steels are worth paying for on this family. When a unit has run hot, the old plates come out blued and coned. Reusing them with new frictions creates hot spots that glaze the new lining within a few thousand miles.
Sonnax documents that the EPC circuit on this valve body wears and leaks at several points, and that the result can be delayed reverse, 1-2 or 2-3 flares, harsh shifts after a kickdown, and even broken bands and blown servo seals. A leaking coast clutch valve can also take out fourth, fifth or engine braking. All of these can mimic worn clutches. If the fluid is still red and the magnet is clean, look at the valve body and solenoids first; the 5R55 harsh or delayed shift walkthrough explains how to split a pressure fault from mechanical wear. If the fluid is burnt and full of debris, rebuild the unit, and repair whatever caused the burn while it is apart.
FM-43 is listed for Ford 4R44E, 4R55E, 5R44E and 5R55E transmissions from 1997 through 2003. It does not fit the later 5R55W or 5R55S, which have different internals despite the similar name; the 5R55S vs 5R55W guide explains that later split. Sonnax also warns that there have been many valve body, plate and solenoid changes since 1995. Before you install, compare the new separator plate gaskets to your plate hole for hole, and compare tooth counts on the old frictions. If you are unsure which unit you have, send us the year and VIN. Other parts for this family are on the 5R55 parts page.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
If it has the 5R55E, yes. That unit was used behind the 4.0L SOHC through this period. The kit is listed for 1997-2003 4R44E, 4R55E, 5R44E and 5R55E. It does not fit the later 5R55W or 5R55S. Send us the VIN if you are not sure.
No. FM-43 includes frictions, steel plates, gaskets, seals and O-rings. Bands, a filter, bushings and solenoids are separate, so inspect them during teardown.
On a unit that has run hot, the old steels are usually blued and slightly coned. New frictions against warped steels glaze quickly, so replacing both sets together avoids doing the job twice.
Yes. The listing covers the 4R44E and 4R55E as well as the five-speed versions for 1997-2003. Compare the separator plate gaskets to your plate before installing, because Ford changed plates several times.
Mercon V. Flush the cooler and lines so old fluid and debris do not reach the new frictions, then set the final level hot.
