I have a 03 F-150 and the four wheel drive doesn't work all the time. Which led me to check the vacuum switch under the pass. side axle. Should i be able to move the lever freely with everything still hooked up?

 

With the actuator motor still in place it makes it difficult to get a grip on the lever. If you suspect the motor use a vacuum pump to test the action.

JMC

 

I can get it to move back in forth and it is working now, I'm just wondering if the actuator is hanging up or sticking sometimes. Is that possible? I think that might be all that is wrong with the 4 wheel drive.

 

It could be the actuator motor that is sticking. Lack of use allows corrosion to build up and it sticks. It could be insufficient vacuum supplied to the motor or it could be internal to the front axle. Now that it is working engage it at least twice a month. Find a slippery spot or a on rainy day slip it into 4x4 and drive a short distance. Disengage it drive a bit more and repeat.

JMC