I have a 97 f-150 4x4. When I shift into 4WD (floor shifter) the light comes on but does not engage. Other threads say it may be a vacuum hose. Where exactly is this located? Any other suggestions would be appreciated. Thanks.

 

Do you get any noise or grinding or anything when you try to engage 4x4?
The vacuum hoses for the center axle disconnect on the front end run down from solenoids near the battery to the center axle disconnect which is near the middle of the front diff, under the plastic cover that oil drains off when you change your filter.

 

I don't get any noise at all. I'll take another look and see if I can find the hoses. Thanks for the help!!

 

I located the solenoids and the vacuum hoses. There are 2 vacuum hoses that run from the solenoids to the center axle disconnect. One has suction and one does not. Are they both supposed to have suction? I made sure the hoses were connected with no breaks in them. Any other advice would be appreciated. Thanks. Steve.

 

They should not have vacuum at the same time. One is for engaging the front diff, the other is for disengaging. I had a similar problem on my 98. In my case there was some vacuum when it engaged, but not enough due to a small leak. I would assume you can tell which is which by checking vacuum while someone turns the swith to 4X4 and back.

 

I have s similiar problem with my 2000 f150. It is a switch type 4x4 on the dash. The light comes on and it will go into 4 low but not 4X4 any ideas on what the problem is??
Adrian

 

Adrian,

Had the same problem with my '01...Dash mounted switch would allow switching to 4x4 low range, but I had no 4x4. Assumed it was the front axle vacuum motor disconnect, but that checked out. So I gambled on replacing the electric transfer case shift motor on the transfer case and that fixed the problem...

 

Thank you for the info, could you possible get me a part number off your old motor? I am in the Philippines and they just don't have a grip on this when I try to explain it to the dealer. My truck is built in the States for Export and they have a dealer here but the mechanics aren't up to speed. I took the truck in for a service last week telling them about the problem and they gave it back saying it is all ok, when I took the shop foreman out to test it he would turn the wheels and drive ahead slowly and say the front tires are turning!!!! To get him to understand I put it in 4 low and floored it and the back tires would spin like carzy and the front nothing and he says "oh it dosen't work". Thanks for this if you can get it if not I will try another avenue.
Regards, Adrian