5R55W Valve Body, remanufactured and ready to install. Fits the 5R55W. Ships fast from the USA.
A 2002-2003 Explorer or Mountaineer that delays going into gear once it's warm, binds momentarily in reverse, or flares on a shift is a textbook 5R55W complaint, and on this unit the part actually causing it is almost always the valve body rather than the solenoid pack bolted to the bottom of it. This is a remanufactured, bench-ready 5R55W valve body, so you install a known-good hydraulic unit instead of diagnosing worn control-valve bores and servo pin wear one symptom at a time.
Ford's own diagnosis manual describes the 5R55W as a 5-speed unit with a 4-element torque converter, three compound planetary gear sets, three bands and three multi-plate clutches, all timed through the valve body. Four on/off shift solenoids position the valves, while three variable force solenoids - PCA, PCB and PCC - modulate pressure during the actual gear engagement: a control valve holds mainline pressure out of the clutch drum while a modulated fill stage builds, then strokes open once PCM amperage drops far enough. A worn valve body either strokes that handoff too early (harsh) or can't build enough modulated pressure to ever stroke it (delayed).
GEARS documented a 2006 Explorer case where a severe delayed-forward complaint, with every solenoid and sensor reading normal, turned out to be a leak at an end plug on the valve body itself rather than anything electrical - a reminder that clean scan data does not clear the valve body. Our servo pin bore wear guide covers the related case-wear failure that produces the same delayed and flared symptoms, and the 5R55 harsh and delayed shift walkthrough covers the wet-air bench test that grades a valve body directly instead of guessing from codes.
This valve body is built for the 5R55W as Ford used it specifically in the 2002-2003 Explorer and Mountaineer, before the Explorer and Mountaineer moved to the 5R55S for 2004-2005. The W and S share a platform and look nearly identical from outside, but Sonnax documents the overdrive sun gear as the real hard-part difference - 24 teeth on the W versus 38 on the S - so confirm which one is actually on your vehicle using the transmission code on the driver's door certification label and the service tag on the case rather than assuming by year alone; our 5R55 identification guide walks through reading both. The full 5R55 parts collection covers everything else we stock for this platform.
Drop the pan and filter with the valve body swap so debris from the old unit does not circulate into the new one, torque the solenoid body bolts to 71 lb-in (8 Nm) in sequence rather than corner to corner, and refill with Mercon V ATF through the T30 torx check plug using Ford's pump-fill procedure - there is no dipstick on this unit, and overfilling is the leading cause of a converter-housing leak that isn't actually a leak. Confirm your solenoid pack revision before reusing it: 2002-2003 units take the early pack, part 1L2Z-7G391-AG. A new or re-primed 5R55W solenoid kit is worth installing alongside the valve body if the original complaint included a stored solenoid code, and the ATF fill adapter makes setting the level correctly on the first try much easier. Clear codes and run the PCM's adaptive relearn afterward so the computer re-times clutch fill against the new unit instead of the worn one.
| Fits | 5R55W |
| Part type | Valve Body |
| 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.
The 5R55W is specific to the 2002-2003 Explorer and Mountaineer; the 5R55S took over for 2004-2005. They share a platform but the overdrive sun gear differs (24 teeth on the W, 38 on the S) and not every part interchanges. Confirm with the transmission code on your door certification label and the case service tag.
Delayed engagement into drive or reverse that's worse when warm, harsh or flared shifts (especially 1-2), a momentary bind in reverse, and ratio codes 732/733/735. Clean scan data does not rule out the valve body - a documented case had every electrical reading normal with a valve body leak as the actual cause.
2002-2003 Explorer and Mountaineer units take the early pack, Ford part 1L2Z-7G391-AG. Confirm your build year before reusing or ordering a pack, since the later 9L2Z-7G391-A pack used on 2004-on W/S units outputs different pressure.
Mercon V ATF. There is no dipstick - level is set from a T30 torx plug in the pan using Ford's pump-fill procedure.
Clear codes and run the PCM's adaptive relearn so the computer re-times clutch fill against the new valve body instead of the worn one.
Recheck fluid level first since overfilling and underfilling both mimic a bad valve body, then check for a leak at the valve body end plugs - a documented 5R55W case had exactly that cause with every solenoid and sensor reading normal.
