This 5R110W Torque Shift Transmission is out of a 2008 F250 crew cab with a 6.4L diesel. Within the 5R110W transmission there are seven solenoids: four shift solenoids with the same part number, a coast clutch solenoid and a direct drive solenoid which have the same part number, and one line pressure control solenoid with a different part number (seven total solenoids but only 3 part numbers). All but one solenoid can be replaced without removing the valve body. However, the line pressure control solenoid requires the valve body to be removed before replacing it. Replacing a shift solenoid on these transmissions is relatively straight forward. Start by removing the transmission pan, draining the fluid into a suitable container, and removing the transmission filter (it pulls straight down). Once removed you’ll see the below pictures.
Removing the individual solenoid consists of disconnecting the two wire connector and removing the C-clip clipped onto the valve side of the solenoid.
Slide the solenoid out of the valve body and lay it on a flat area for testing.
If the solenoid is questionable then you can quickly bench test the solenoid using a multi-meter and 12V battery. Turn the multi-meter to ohms and check the resistance between the two pin terminalswhich should be between 4.1-4.7 ohms. Next check the resistance from each pin terminal one at a time to the metal body of the solenoid to verify there is not a short to ground (any reading other than OL means there is a short to ground and the solenoid needs replaced). Finally, connect jumper wires from the two solenoid pins to a 12V battery (negative battery terminal to one lead and positive battery terminal to the other) and connect and disconnect the positive jumper wire at the battery to verify the piston inside the solenoid is pumping out transmission fluid (you’ll see it squirting out the valve side of the solenoid if it is working correctly).
To finish up, install the new solenoid, install the transmission filter (good idea to go ahead and replace it with a new one),
transmission pan and gasket, and then fill and check the transmission fluid level.
A quick summary of the 5R110W transmission off of http://www.trucktrandiag.com is that it is a five speed transmission, with technically six gears, that is computer controlled with a lock-up torque converter clutch. In “cold mode” (under 5 deg. F.) the unit shifts 1-2-3-4-6. In “hot mode” (over 5 deg. F.) the unit shifts 1-2-3-5-6 with torque converter clutch. The gear ratios are: 1st 3.09, 2nd 2.20, 3rd 1.54, 4th 1.09, 5th 1.00, and 6th 0.71 (overdrive). In limp mode there will be certain trouble codes and/or total loss of power to the transmission resulting in use of only reverse and 5th gear.