triton54

i bought a 2006 4x4 5.4 f150. while driving today i noticed a grinding noise when i backed up. i thought there was something dragging. got out and and looked and there was nothing. jumped back in and put the truck in drive. there was then a grinding noise in forward motion. i slowed down and the noise stopped. i came home and ;looked on this site and it said to try and shift in to 4x4 i went out tried to shift into 4x4 and nothing works. the 4x4 wrked when i purchased the truck 3 weeks ago., please help.

triton54

the truck is electronic shift. also no lights appear when i try switching.

triton54

if anyone has any idea please reply

mgidaho

Your 4x4 system is actuated by a vacuum. I know that if this vacuum is lost the hubs will try to lock into place. This might explain your grinding noise. I would take a look at your whole 4x4 system to see if anything looks out of place. Start by looking just behind your brake rotors. It might be something as simple as a vacuum line coming free. Then inspect farther into the center of your truck and your 4x4 system.

Hope this helps!

Busker444

I would suggest searching some of the other threads here about 4x4 switching/grinding problems. On the first page, look at the thread with IWE in the title. I am having an issue with my 4x4 light indicator not working and have posted a query. But I did read that thread and several others and tried some of the suggestions listed there. See you over there and maybe we will both get some good advice.

In fact, here is another good thread on this issue.