5R55S Pump 2001, remanufactured and ready to install. Fits the 5R55S. Ships fast from the USA.
Explorer, Mountaineer, Mustang V6, Lincoln LS and Thunderbird owners usually land on a 5R55 pump after the same story: the truck or car is fine cold, but once it is hot it sits in gear for a second or two before it moves, there is a whine that follows the tach, and the transmission feels soft everywhere. This is a remanufactured complete front pump for 2001-and-up 5R55W, 5R55S and 5R55N transmissions, listed under Ford service number 5L2P-7B325-AA. It arrives as a full assembly with the pump body and stator support, ready to bolt in.
The pump gears are turned by the converter hub, so the pump only makes as much volume as engine speed allows. At idle with hot, thin fluid, a worn gear pocket or a leaking line control valve cannot keep up, and that is when engagement suffers. The pump also feeds the converter: Sonnax explains that converter release oil is held to about 130 psi by the converter regulator and then flows to the cooler, while line pressure in these units runs from roughly 160 to over 250 psi. A tired pump drags all of those circuits down at once, which is why the symptoms show up in every gear rather than on one shift.
Sonnax describes a simple flow check: with the unit at operating temperature, if cooler flow is always low out of lockup and drops sharply in Reverse, suspect the pump line control valve, pump misalignment or a worn gear pocket. A line pressure gauge reading low in every range backs that up. On the bench, 100 psi of air into the line control circuit that makes a pop means the plunger is stuck. Rule out the common 5R55 servo bore and valve body problems too; our 5R55S pump failure guide and whine and clunk diagnosis guide cover the differences.
This pump is listed for 2001 and later 5R55W, 5R55S and 5R55N transmissions. Sonnax dates the 5R55W to 2002-2003 Explorer and Mountaineer, with the 5R55S taking over in 2004-2005, and the 5R55N to 1999-2002 Lincoln LS, Thunderbird and Jaguar S-Type before the S replaced it in 2003. Because the N shares only a few parts with the W/S, and the W and S use different overdrive sun gears, match the pump body and stator support on your old unit to the photo, or send us your year and VIN and we will confirm it. Earlier 5R55E applications are not covered. The 5R55S vs 5R55W guide and our 5R55 collection will help you narrow it down.
| Fits | 5R55S 2001 |
| Part type | Pump |
| Condition | Remanufactured |
| 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.
It is listed for 5R55W, 5R55S and 5R55N transmissions from 2001 on, used in Explorer, Mountaineer, Lincoln LS, Thunderbird, Jaguar S-Type and later Mustang V6 models. Send your year and VIN if you are unsure which version you have.
Yes. It is a remanufactured complete pump assembly, listed under Ford number 5L2P-7B325-AA, not a gear set or a rebuild kit.
A dry fill is about 11.2 quarts behind the 3.0L and 3.9L engines and 12.4 to 12.7 quarts behind the 4.0L and 4.6L. Use Mercon V and check the level hot at the fill plug.
Yes. Hot fluid thins out and leaks past worn pump clearances and a sticking line control valve, so pressure builds slowly at idle. Raising the rpm temporarily hides it.
Clear the adaptive values with a scan tool and drive the vehicle through normal shifts so the computer can relearn clutch fill times.
