My 2000 F150 is into its 5th Vermont winter (the skiing's great!). Two maladies arrived with the cold weather:
1. The mechanical 4WD lever is tough to move.
2. After shifting from 4-HI to 2-HI, a rumbling noise and stiff steering say it's not completely out of 4WD, even though the lever's all the way forward and the 4WD light goes out. I need to hit a road bump or stop and reverse to disengage completely.
Anyone got a remedy?

 

Hello mpeal,

This may help if you have not done so recently, change the fluid (using synthetic fluids may also help in cold weather) in your transfer case and front axle and make sure all the linkage is lubed.

 

mpeal,

Like was mentioned by rkjerue, lube the linkage to the T-case and the front Actuator motor. It is exposed to the elements and can get dirty and make shifting difficult. The front disengaging can be caused by 4 things. Loss of vacuum to actuator motor, faulty motor, binding linkage or internal differential problems.
Because engages when you shift into 4x4 and it requires a bump or driving in reverse to fully disengage I would suspect a faulty actuator motor or vacuum supply.
There are 2 solenoids that control vacuum to the actuator motor. They are located on the passenger side of the firewall behind the battery. With the engine running check for vacuum to these solenoids. There should be vacuum. With the key on engine off shift into 4hi then disconnect the feed line to the solenoid with the red line and apply vacuum to the solenoid. It should hold vacuum, switch back into 2hi. Try the test again. It should not hold vacuum. Reconnect it and test the other solenoid. It should hold vacuum in 2 Hi. Switch back into 4Hi and it shouldn’t hold vacuum. If the solenoids fail any of the test, replace the solenoids that fail. If they test out OK check the lines from the solenoids to the actuator motor. Replace them if they fail. If they are ok you are left with the Actuator motor or the differential. Disconnect the Actuator motor from the linkage and shift into 4 Hi. Check to see if the actuator motor moves. Then back to 2hi. Check again If it does then the problem is in the front differential.

Regards

Jean Marc Chartier

 

To rkjerue and JMC~
Now it's time for me to pull on my down-filled snowsuit, crawl underneath, and follow your wise advice.
Thanks, indeed, for the wealth of info.