5R110W Internal Wiring Harness 2003-2017, remanufactured and ready to install. Fits the 5R110W. Ships fast from the USA.
This remanufactured internal wiring harness is listed for 5R110W TorqShift transmissions from 2003 through 2017, covering the Super Duty pickups and chassis cabs, the Excursion and the E-Series vans that used this five-speed. Buyers usually land here after chasing a TorqShift that sets random electrical codes, will not hold a gear when hot, or reads a fluid temperature that makes no sense, and after the solenoids themselves have tested good.
Inside the pan, the 5R110W is controlled almost entirely by electricity. Each clutch except the forward clutch has a dedicated variable-force solenoid, and line pressure and the converter clutch each get their own, for seven in all. Ford's design leaves no shift valves to fall back on, so if a solenoid loses its feed the clutch it controls loses its pressure command. The internal harness is the bridge between the case pass-through connector and all of those parts. It also carries the transmission fluid temperature signal, which the computer uses to switch into the cold-mode shift schedule below about 5 F, and the signal from the internal range sensor that tells the computer which gear the lever is in.
Start outside the transmission. A truck that sets a spread of unrelated codes may have a problem in the main harness or at the computer, and on 6.0L trucks a leaking water-in-fuel sensor can push diesel up the harness into the computer connector. Once the outside checks clean, pull the pan, unplug a suspect solenoid and compare its resistance at its own pins with the reading through the case connector. A good solenoid behind a bad reading means the harness. If the solenoid is the bad part instead, our 5R110 solenoid testing guide covers identification and replacement, and a 2004-2017 5R110W solenoid kit is listed for the same years.
Listed fit is the 5R110W for 2003-2017. Most buyers will have a 2003-2010 F-250 through F-550 Super Duty with the 6.0L or 6.4L Power Stroke or a gas V8/V10, an Excursion, or an E-Series van. The span is wide and Ford revised the solenoid body along the way; Sonnax documents that early bodies used one or five pressure switches and that Ford dropped them in late 2004. Before installing, match the connector count, plug styles and pass-through shape to the harness you are removing. If you are unsure, send us your year and VIN and we will check it. Every other 5R110W year and part we carry is on the 5R110W collection page, along with our separately listed 5R110W internal harness.
Plan for a pan drop and a fresh filter. Photograph the old harness in place before you unplug anything so the routing and clip points go back the same way. Push the case connector in from the outside after releasing its retainer, then feed the new connector out and seat its seal fully so it cannot leak at the case. Snap each plug until it locks, and keep wires clear of the filter and pan rail. A TorqShift filter kit covers the filter and gasket. Fill with MERCON LV, which Ford authorized for these units in place of the original MERCON SP, and verify level hot. If the battery was disconnected, perform Ford's engagement relearn with the fluid at 130 F before handing the truck back. Our 5R110 TorqShift service guide covers the fluid and remote filter details.
| Fits | 5R110W 2003-2017 |
| Part type | Internal Wiring Harness |
| 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 2003-2017, but Ford revised the solenoid body over that span, including dropping pressure switches in late 2004. Match connector count, plug styles and the pass-through to your old harness, or send your year and VIN for a check.
Only if they test bad. Measure each solenoid at its own terminals. If the readings are good and the faults follow the wiring, the harness alone is the fix.
Below about 5 F on the fluid temperature sensor, the 5R110W runs a cold-mode schedule that is normal. If it does this when warm, or never does it in the cold, check the TFT circuit, which runs through this harness.
If the battery was disconnected, yes. Warm the fluid to 130 F and perform five each of Park to Reverse, Drive to Reverse, Reverse to Drive and Neutral to Drive engagements, five seconds apart.
Ford authorized MERCON LV for complete refill and top-off of the 5R110W, which was originally filled with MERCON SP. Check the callout for your VIN.
