4R44E Overhaul Kit 1997-2005, new and ready to install. Fits the 4R44E. Ships fast from the USA.
This listing is the Precision International KP53900T transmission overhaul kit, new in the maker's package, for the 4R44E, 5R44E and 5R55E built from 1997 through 2005. Shoppers land here with a Ranger, Mazda B-Series, Explorer or Mountaineer that is dripping ATF, flares between gears when hot, or is already out of the truck with the case split. KP53900T is a reseal package: the gaskets, seals, O-rings and sealing rings that keep oil inside each circuit. Clutch plates, bands, the filter and bushings are bought separately.
Every shift in a 4R44E is hydraulic. The computer only sends a signal to the shift solenoids and the EPC solenoid; the valve body turns that signal into oil pressure, and the oil travels through the case, pump and drums to the clutch pistons and servos. Each joint along that path relies on a gasket or seal. Sonnax points out that leaks in the EPC circuit are behind several common complaints in this family, including flares on the 1-2 or 2-3 shift, harsh shifts after a kickdown, broken bands and blown servo piston seals. Replacing the sealing parts restores the pressure each apply circuit is supposed to see, which is why a reseal is the base of every rebuild on this unit.
Put a gauge on the line pressure tap before ordering parts. Low pressure in every range points to the pump, the EPC solenoid or a big internal leak, while low pressure in one range points to that circuit's seals. Our guide to checking transmission line pressure covers hook-up and how to read the numbers. While the valve body is off, the Sonnax vacuum test guide for this family shows which bores to test; if they fail, the Sonnax 4R44E/5R55E Zip Kit or a replacement 4R44E valve body has to go in with the seals or the complaint returns.
KP53900T is listed for 1997-2005 4R44E, 5R44E and 5R55E transmissions, and the kit is catalogued for Ford, Lincoln, Mazda and Mercury applications. In practice that means the Ranger and Mazda B-Series small-engine automatics and the 4.0L Ranger, Explorer, Sport Trac and Mountaineer through 2005. It does not fit the 5R55W or 5R55S, which are different transmissions. Check the transmission code on the door tag and compare your old gaskets to the new ones before assembly. If your truck is a 2006 or later build, look at our 1997-2011 4R44E overhaul kit instead. You can find everything for this family in the 5R55 and 4R44E collection, and you can send us your year and VIN if you want us to check fitment.
If the shift solenoids are original, the 1997-2011 4R44E solenoid kit is worth adding to the same order, since the pan and valve body are already off.
| Fits | 4R44E 1997-2005 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | OEM |
| Reference | KP53900T |
| Ships | From the USA |
| Warranty | 1-year |
It is an overhaul kit: gaskets, lip seals, piston seals, O-rings and sealing rings. It does not include frictions, steels, bands, a filter or bushings.
Only if that Explorer has the 5R55E, which was used in the Sport Trac and the two-door Sport. Most 2002-2005 four-door Explorers use the 5R55W, which this kit does not fit.
Yes, for 1997-2005 builds. The 4R44E, 5R44E and 5R55E from those years share the sealing set covered by KP53900T.
The computer adapts shift pressure as it drives. Disconnecting the battery clears old adaptive values, then a normal mix of light and moderate shifts lets it relearn.
Only if it passes a vacuum test. Worn bores and loose end plugs leak oil just like a bad seal, so a worn valve body will bring back the same symptoms after the reseal.
