5R55W Overhaul Kit 2005-10, new and ready to install. Fits the 5R55W. Ships fast from the USA.
Owners of a 2002-2004 Ford Explorer or Mercury Mountaineer with the 5R55W tend to land here after the same story: the truck slips going up a grade, Reverse takes a moment to bite, or there is a ring of red fluid under the bellhousing every morning. When the unit is coming apart, this Transtec 46002C overhaul kit supplies the sealing parts. It is the same kit sold for the 5R55S through 2010, which is where the 2005-10 in the title comes from; the 5R55W itself is listed for 2002-2004. The kit carries gaskets, lip seals, sealing rings and O-rings, and it ships without pistons.
The W is the Explorer and Mountaineer version of the five-speed, with a 24-tooth overdrive sun gear according to Sonnax. Like the S, every apply is hydraulic: the solenoid body meters oil to the clutches and to the overdrive, intermediate and low/reverse servos, and the oil has to stay sealed the whole way there. Sealing rings on the input and output shafts feed the rotating clutches, while the case and pan gaskets keep the circuits from bleeding into each other. When those parts harden or nick, clutch apply slows down and the truck shifts late, soft or not at all. A complete reseal is the baseline for any W rebuild.
The W has two well-known non-seal failures. Worn overdrive and intermediate servo pin bores let apply oil escape in the case, which Sonnax fixes with a sleeve kit, and a stuck low/reverse servo control valve on its own causes delayed reverse. Read the servo pin bore wear guide and our 5R55W Explorer slipping guide before ordering, then use the 5R55 delayed shift walkthrough to rule out solenoids and wiring. If the leak is simply external, the 5R55W leak locations guide can save you a full teardown.
The 46002C is listed for the 5R55W from 2002 to 2004, the 5R55S from 2002 to 2010 and the 5R55N from 2000 to 2002. For W owners that means 2002-2004 Explorer and Mountaineer models; Sonnax puts the W in those trucks for 2002-03 before the S took over, so a 2004 can be either. The quickest way to tell the units apart in hand is the overdrive sun gear tooth count, 24 for the W and 38 for the S, but the seals in this kit are shared either way. Check the door-jamb transmission code or send us your year and VIN, and see the full lineup on the 5R55 parts page. A W-specific seal set is also available as the 5R55W gasket and seal kit for 2002-2010.
| Fits | 5R55W 2005-10 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The kit is shared with the 5R55S, which ran through 2010. For the 5R55W itself the kit is listed for 2002-2004 Explorer and Mountaineer applications.
Yes, the 46002C is listed for both, plus the 2000-2002 5R55N. The hard parts differ, such as the overdrive sun gear, but the seals and gaskets in this kit are shared.
No. It is the seal and gasket set without pistons. Frictions, steels, bands and the filter are sold separately.
Only if leaking seals are the cause. Worn servo pin bores and a stuck low/reverse servo control valve are common causes in the 5R55W and need their own repair.
The installation guide lists about 12.4 to 12.7 quarts of Mercon V from dry behind the 4.0L or 4.6L. Set the final level hot at the fill plug.
