F150 4x4 not working

[blazerbrad]

Originally Posted by Flxratd

yeah its a 150. there not like a normal locking hub its an internal vacum operated (expensive)pos. looks like a unit bearing in design but has a vacum opererated cog ring inside. dont know if that started in 04 since there was a body change but i know my dad wasnt impressed when his 4x4 was only 4x2

Learn something new every day. I knew the Super Duty's had the vacuum hubs that can also be manuall engaged but did not know the F-150s had the vacuum portion of the system.

For the other question, yes I believe it is the solenoid (not sure if where the battery is at) but pretty sure it is on the driver's side firewall area. On my brother-in-laws trucks it would randomly try to engage 4wd while cruising down the road.