4R55E Overhaul Kit 1997, new and ready to install. Fits the 4R55E. Ships fast from the USA.
The 1997 model year is where Ford's 4.0L V6 trucks switched from the four-speed 4R55E to the five-speed 5R55E, and it is also where the seal catalog for this family splits. This overhaul kit is the 1997-and-later gasket and seal set, catalogued as B56002L, for 4R55E, 5R55E, 4R44E and 5R44E transmissions. It is for the Ranger, Explorer, Mountaineer, Aerostar or Mazda B-Series owner whose automatic leaks, engages slowly when cold, or is already apart on the bench for a reseal.
According to The Ranger Station, the 4R55E was short-lived: it went into 4.0L Rangers in 1995 and was replaced everywhere it had been used by the 5R55E during the 1997 model year. Sonnax describes the same change from the rebuilder's side, explaining that from 1997 the front servo was applied to produce an overdriven first and a fifth gear. The case, pump and clutch layout stayed close enough that one 1997-up gasket and seal set covers the four-speed and five-speed units, but an earlier 1995-1996 truck needs the 1994-1996 4R55E overhaul kit instead. A 1997 truck built early in the model year can go either way, so check the transmission code before you order.
Ford built the 4R55E as the heavy-duty sister of the 4R44E for the 4.0L, with a rating of about 550 lb-ft after converter multiplication. The extra torque goes through the same type of hydraulic circuits: clutch pistons and servos that are only as strong as the oil pressure behind them. Every circuit seal and gasket in the unit keeps that pressure where the computer sends it. On a high-mileage 4.0L the rubber hardens, gaskets take a set, and the extra torque turns a small leak into a slipping clutch faster than in the smaller-engine 4R44E. This kit replaces all of those sealing parts in one order.
Read codes and check the fluid first. Burnt, dark fluid with friction material in the pan means the clutches are done, and the 1997 4R55E master rebuild kit is the better buy. Clean fluid with slipping or slow engagement calls for a pressure test; our transmission pressure testing guide shows how to read the gauge in each range and separate a leaking circuit from a weak pump. If the converter clutch is the complaint, read our guide to converter hub and pump bushing wear before blaming seals alone.
The kit is catalogued for 1997-up 4R55E, 5R55E and 5R44E, and the application list covers the 1997-2011 Ranger, 1997 Aerostar, Explorer and Sport Trac with the 5-speed and 4.0L, 1998-2000 Mountaineer, and 1997-2010 Mazda B-Series pickups. It does not fit the 5R55W or 5R55S used in 2002-up Explorers and Mustangs; those are a different design. Confirm the transmission code on the driver door tag or the ID tag on the case, and send us your year and VIN if your truck sits on a changeover. You can see every part for this family on our 5R55 transmission collection.
Pre-soak the rubber seals in clean ATF, lubricate sealing rings with assembly gel, and seat metal-clad seals with a driver that bears on the outer shell rather than the lip. Air-check every clutch and servo circuit before the valve body goes on. If the truck lost a converter or a clutch pack, flush the cooler and lines using our cooler flush procedure so debris does not cut the new seals. Fill with the MERCON-family ATF shown on the dipstick and check it hot. A new 1997-2011 TCC solenoid is worth installing while the pan is down if you had lockup complaints.
| Fits | 4R55E 1997 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
It depends on build date and engine, since Ford moved from the 4R55E to the 5R55E during 1997. Count the forward gears on a drive or read the transmission code on the door tag. This kit covers both, as long as the unit is a 1997-up design.
Gaskets, seals and O-rings for an overhaul. Frictions, steels, bands, a filter and bushings are not part of a basic overhaul kit, so plan on a master rebuild kit if those are worn.
Only if the truck has a 5R55E. Most 2002-up Explorers with the new body use the 5R55W, which is a different transmission and needs different seals.
Use the MERCON-family ATF shown on your dipstick or in your owner guide, and check the level with the engine running and the fluid hot.
Only when the friction material is still good. If the fluid is burnt or the pan has lining in it, the clutches need replacing and a seal kit by itself will not stop the slip.
