I have a 2004 XLT F150 4X4 and the 4WD will not engage. Took it to a reputable tranny guy in town and he told me it works off of vacuum related to the front wheel bearings. One side was locked on, and the other side was locked off. Bearings go for around $350/piece, labor of about 4 hours for an estimate of around $1000. I am mechanically able but would like to know how difficult this replacement would be. Thanks for any help.

 

Sounds like the same problem as this:

https://www.f150online.com/forums/ot...ot-engage.html

Background material:

https://www.f150online.com/forums/ar...then-some.html

https://www.f150online.com/forums/ar...replacing.html

https://www.f150online.com/forums/ar...-pictures.html

Sounds like this guy is taking you for a ride.