Replaces the failed 5R55W and 5R55S solenoid block on Ford Explorer, Mountaineer and Mustang to clear P0745, limp mode and a lost overdrive.
When a 2002-and-later Explorer, Sport Trac or Mountaineer throws P0745 or P0751, loses overdrive, or comes off the line in second with the wrench light lit, the solenoid block on top of the valve body is the usual suspect. The same block lives in the 5R55S behind the 2005-2010 Mustang V6 and GT, the 2003-2006 Lincoln LS and the Aviator. This listing is a remanufactured block built from an OE core and tested, referenced to Ford 9L2Z-7G234-AA and 9L2Z-7G391-AA, so the whole electrical control assembly is renewed at once.
There are no throttle cables or governors in this five-speed. Every gear change is a command from the PCM to a solenoid on this one block. Transmission Digest counts eight coils on it: four on/off shift solenoids, a pulse-width TCC solenoid and three variable force solenoids. The variable force units are the ones that wear out. ATRA's seminar notes show how small the margin is: a 4 psi change in PCA output at 0.6 amp works out to about 30 psi of mainline difference, which is the gap between a crisp shift and a flare or a bang. As the windings heat-cycle and the valve bores in the block wear, the PCM keeps adapting until it runs out of range and sets a code.
Keep the model's other known faults in mind. Fifth-gear slip with P0735 is normally overdrive and intermediate servo pin bore wear in the case, and worn intermediate or overdrive bands will slip no matter how good the solenoids are. A new block does not fix either.
Read every stored and pending code and note the order they set. Look at the fluid: dark, burnt fluid with friction material in the pan points to hard-part damage. Check the case connector for oil wicking into the external harness, and measure solenoid resistance through the connector if you have the specifications. Our 5R55 harsh and delayed shift walkthrough separates block faults from servo bore and band problems, and the 5R55S shift solenoid symptoms guide lists what each solenoid circuit controls.
The listing covers Explorer, Explorer Sport Trac and Mountaineer 4.0L and 4.6L from 2002 on, Mustang 4.0L and 4.6L 2005-2010, Lincoln LS 3.0L and 3.9L 2003-2006 and Aviator 4.6L 2003-2006. It does not fit the 5R55E four-cylinder and V6 Ranger unit, which uses separate solenoids, or the 5R55N in the 1999-2002 LS and Thunderbird. ATRA notes that Ford's early pack, 1L2Z-7G391-AG, went into 2002-2003 Ford units and the 2003 LS, with the late pack used from 2004; the packs do not deliver identical pressure, so 2002-2003 owners should compare the number on the old block or send us the year and VIN. Everything else for this family is on our 5R55 parts page.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. The 5R55E in the Ranger and B-series uses individual solenoids and a different valve body. This block is for the 5R55W and 5R55S only.
Remanufactured from an OE core and tested, referenced to Ford 9L2Z-7G234-AA and 9L2Z-7G391-AA, with a 12 month warranty per the listing.
Pressure control and shift solenoid faults such as P0745, P1746, P0751, P0752 and P0761. A P0735 fifth-gear ratio code is more often servo pin bore wear and is not fixed by the block.
Mercon V. A pan drop only replaces part of the fluid, so add a few quarts, start the engine and set the level hot at the fill plug rather than going by a fixed number.
Yes. Clear the codes and reset or relearn the transmission adaptives so the PCM stops compensating for the old block.
