4R100 Pressure Control Solenoid, used and ready to install. Fits the 4R100. Ships fast from the USA.
If your 7.3L Power Stroke or V10 Super Duty slams into every gear, or goes soft and gutless with a flashing overdrive light and an EPC code like P1746 or P1747, you are probably shopping for a 4R100 pressure control solenoid. Ford never sold that solenoid on its own for this transmission. It lives inside the solenoid pack, and this listing goes a step further: it is a used original Ford three-piece hydraulic set, made up of the main control valve body, the accumulator body and the PWM-style solenoid pack marked F81P-7G391-CC. It was removed from a working transmission and tested before it ships.
The 4R100 has no throttle valve cable and no vacuum modulator. Line pressure is set entirely by the EPC solenoid, a variable force solenoid that the PCM feeds a changing current. That current becomes a signal pressure acting on the line pressure modulator valve, which works the main regulator in the pump. It runs backwards from what most people expect: more current means less pressure, and zero current means maximum pressure, so a broken wire leaves the truck shifting hard instead of burning its clutches. ATSG lists EPC as modulated in every gear, calculated from throttle, engine load, turbine and output speed, fluid temperature and range position. The same pack also carries shift solenoids 1 and 2, the coast clutch solenoid, the converter clutch solenoid and the fluid temperature sensor, and ATSG notes none of them are serviced individually.
With the key off, the EPC coil reads across pins 11 and 12 of the solenoid connector and should be 3.0-5.0 ohms; the shift and coast clutch solenoids read 20-30. Then backprobe the case connector on a road test and put a gauge on the line pressure tap. Do not skip the computer. Transmission Digest documented a 2002 F-550 with P1747 that had already received a new pack and pedal sensor; the real fault was a failed EPC driver inside the PCM. Our EPC solenoid symptoms guide walks through every test and the pressure chart, and the valve body testing guide covers the modulator and regulator wear that mimics a bad solenoid.
The listing covers 1998-2004 4R100 trucks; ATSG dates the 4R100 to the 1999 model year, with production starting in 1998. The interchange named on the source unit includes F-250 through F-550 Super Duty, Excursion and E-Series vans with the 5.4L, 6.8L V10 or 7.3L Power Stroke. The detail that matters most is converter clutch strategy. ATSG explains that the 4R100 was built in a PWM version for V10 gas and all diesel engines and a non-PWM version for the other gas engines, with different solenoid packs and different pumps. This set carries the PWM pack, so it lines up with 7.3L and 6.8L trucks; a 5.4L truck with the on/off converter clutch pack is a different combination. Because castings changed across these years, compare the numbers on your valve bodies and pack, or send us your year and VIN before ordering. It will not fit an earlier E4OD. The full E4OD and 4R100 parts page lists the rest of the family, and our 4R100 vs E4OD comparison explains the changes.
| Fits | 4R100 |
| Part type | Pressure Control Solenoid |
| Condition | Used |
| 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.
Not as a Ford part. The EPC solenoid is built into the solenoid pack with the shift, coast clutch and converter clutch solenoids and the fluid temperature sensor, and the pack is replaced as one assembly. This listing includes that pack plus the main and accumulator valve bodies.
Probably not as-is. This set has the PWM solenoid pack, which ATSG ties to V10 gas and diesel 4R100s. Most 5.4L trucks use the non-PWM pack and pump. Send us your year and VIN and we will check.
It might be, but check the PCM too. P1747 is a short in the EPC circuit or the PCM driver. Measure the coil at 3.0-5.0 ohms and check the signal at the case connector before buying parts.
No. It is an original Ford assembly removed from a running transmission and tested before shipping. Match your casting numbers before you order.
Mercon V. Set the level with the dipstick at normal operating temperature, 150-170 F, with the engine idling in Park.
Always the filter and pan gasket. Clean or repair the case connector, and if you are changing between PWM and non-PWM packs, the pump has to match.
