5R55S Valve Body, remanufactured and ready to install. Fits the 5R55S. Ships fast from the USA.
A 5R55S that bangs into reverse, takes a few seconds to find drive once warm, or flares on a shift is usually a hydraulic problem living inside the valve body, not an electrical one - and reaching for a solenoid pack first is the most common way to spend money without fixing it. This is a remanufactured, bench-ready 5R55S valve body, built so you install a known-good hydraulic unit instead of diagnosing worn bores and a tired separator plate piece by piece.
The 5R55S carries four on/off shift solenoids, one PWM solenoid for the torque converter clutch, and three variable force solenoids - PCA, PCB and PCC - that modulate pressure through the valve body during the actual gear engagement, not just the static, already-engaged circuit shown in the factory hydraulic diagrams. Per Transmission Digest's breakdown of the engagement sequence, reverse and forward each depend on a two-stage handoff: a modulated VFS pressure holds an engagement control valve closed while the clutch drum fills slowly, then as PCM amperage drops, pressure rises until it strokes the valve and dumps mainline straight into the drum. Harsh means that handoff came too early or too hard; delayed means the modulated stage never built enough pressure to fill the drum, or the control valve itself cannot stroke.
Gear-ratio codes 732/733/735 on this unit usually point to servo and band control rather than a burnt band outright, and our 5R55S valve body symptoms and testing guide walks through the wet-air bench test that grades the valve body directly rather than guessing from codes alone. If the complaint is specifically a slow reverse, check the low/reverse servo control valve first, since it fails independently and gets missed during a lot of rebuilds - our servo pin bore wear writeup covers that failure and the case-salvage fix in depth.
This valve body is built for the 5R55S as Ford used it in the Lincoln LS and Thunderbird from 2003 on, and in the Explorer and Mountaineer for 2004-2005 before later V6 Explorers and the 2005-2010 Mustang carried it as well. The S and W share a platform and outward appearance but not every part - Sonnax documents the overdrive sun gear as the key hard-part difference, 38 teeth on the S versus 24 on the W - so on an overlap-year Explorer or Mountaineer, confirm which one you actually have with the door-jamb transmission code and case service tag before ordering; 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 at the same time as the valve body 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, using Ford's no-dipstick fill procedure through the T30 torx check plug rather than guessing a level. Confirm the solenoid pack revision matches your build year before reusing it - 2004-on units take the updated 9L2Z-7G391-A pack, and mixing an early pack onto a late valve body can itself cause soft 2-3 flares. Pair the swap with a 5R55S shift kit if you also want firmer, more consistent shift feel, and clear codes and run the PCM's adaptive relearn afterward so the computer re-times clutch fill against the new unit.
| Fits | 5R55S |
| 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 5R55S and 5R55W share a platform and look similar, but the overdrive sun gear differs (38 teeth on the S, 24 on the W) and they don't share every rebuild part. Read the transmission code on your door certification label and the service tag on the case to confirm which one you have before ordering.
Harsh or flared shifts (especially 1-2 and 2-3), delayed engagement into drive or reverse that's worse when warm, slipping between gears, and ratio codes 732/733/735. A wet-air bench test on the valve body separates a hydraulic fault from a solenoid-only one.
Lincoln LS and Thunderbird from 2003 on, Explorer and Mountaineer for 2004-2005, later V6 Explorers, and the 2005-2010 Mustang.
Mercon V ATF. There is no dipstick - level is set from a T30 torx plug in the pan using Ford's pump-fill procedure, not by checking a stick.
Match the pack to your build year. 2002-2003 units take the early pack (1L2Z-7G391-AG); 2004-on units take the updated 9L2Z-7G391-A. Mixing an old pack onto a newer valve body can itself cause soft or harsh shifts.
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.
