Please help , when engaging 4x4 in truck, light indicates that the
I am in 4x4 mode , yet only my rear wheels engage . The electrical system is working . Is there a problem with the vacumn
and any suggestions on how to repair it. I get a lot of snow up here , and that one of the reasons I enjoy this truck .
Please some one help . Thanks Eli

 

Are you sure the T-Case is engaged when you shift into 4x4? With tranny in park and front of the truck off the ground so the wheels are free to turn engage 4x4 and try to turn the front drive shaft. It should not turn. If it does the problem is in the T-case. Have you checked the vacuum lines for leaks? Is there vacumm at the blue line when in 4x4? Is the shift actuator in the front axle moving when engaging 4x4?

Regards

Jean Marc Chartier

 

Thank You JMC for responding so quickly .

I had the truck up on a lift recently we engaged the 4x4,and the front wheels did not turn , my mechanic Gilbert mentioned something to the effect that I had vacumn on both sides of the
vacumn shift motor . My F-150 is a MSOF transfer case .
You 've got me with the vacumn at the blue line in 4x4 ?
I will try what you mentioned , I'll recheck the vacumn lines .
I'll try the front wheels idea ,I'll block the wheels in some manner
for mine is a manual shift .

An thank you again for giving me some ideas , I enjoy doing things myself .
P.S. I noticed in your profile you have a "superchip" does it really help . I only have the 4.2 litre so a little extra boost would be nice .
Any ideas , somethings on the site have really peaked
my interest .
Eli

 

I had the same problem with my 4 wheel drive. There are 2 vacuum control solenoids on the firewall behind the battery where the pink and blue vacuum lines originate. You need to determine which one is malfunctioning, most likely the one for the pink line if both lines are pulling vacuum when 4x4 is engaged. On my truck the vacuum motor looked like it was engaging but the 2 vacuum lines were partially offsetting each other and it would not fully engage.
Ford has the solenoids for about $30 each, easy as can be to replace.
Tom

 

To ttimoney
Thanks , you were bang on about the solenoid . Followed my
vacumn lines , after checking which one wasn't working properly.
I removed one which was cracked and replaced it , just in time for a snow storm up here in Canada . So now I am happy four -footing again . A little more costly up here , but better than having them (ford dealer ) muck around in my truck .

So once again Thanks Eli