four wheel drive
I've read through the manual for my 2004 F250 FX4 and the hubs on my truck dont have any markings on them. This is the way I figured it out; move the hubs in the same direction, either rt or lft, without engaging the 4X4 have somone drive it foward a few feet while you walk along side and look to see if the front drive shaft turns. If it did the hubs are locked. If it didnt move the hubs are unlocked. Hope this helps.
on my 05. i have to turn them clockwise to lock the hubs in, counter clockwise to disengage.
Easiest way I figured it out was to jack up your front end and turn the tire by hand. If the axle rotates then it's locked. If not then turn the lock.
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