My 2004 F-150 4x4 won't engage in 4 wheel drive, it also always whines when I drive in 2 wheel drive but the whine stops when I put it in 4x4. But 4 wheel drive doesn't work, I found that out in the snow we just had...bad time to find out!

Anyway, before now it has made some strange noises when i put it in 4x4, like bumps and other noises, like it is trying to engage, but now it does nothing at all when I put it in 4x4 high or low.

What could it be is it going to be expensive?
Thanks.

 

Sounds like it's either a vacuum problem or the vacuum solenoid...There is an known solenoid issue with the F-150's for thre 4X4...

 

A vacuum problem sounds cheap to fix, is it?

 

Sounds like you have a vacuum seal leaking> If you can remove the hub assembly, the seal is on the backside of it and it takes a special tool to seat the new one.

 

THE SOLENOID SHOULD BE MOUNTED ON OR BY THE FIREWALL ON THE P/S. BEING THAT I DON'T KNOW WHAT SIZE ENGINE IT HAS, I CAN'T LOOK IT UP FOR YOU BUT FOR PRICES GO TO OUR DEALERSHIPS WEB SITE www.discountedgenuinefordparts.combasically everything on the site is set at employee cost.