ok I can put my truck (07 manual 4x4) into 4x4 hi the light comes on but does not engage. i can jack up the front end spin the front wheels and the shafts don't spin in 2hi and 4hi but when i take the vacuum line off the solenid at the fire wall for the 4x4 and the shafts engage and when i spin the wheels. Does this mean that solenoid on the firewall is bad?

 

Yes... but, if you have this solenoid it's not manual 4X4...or is it a manual tranny ??

 

Manual 4x4 does have the solenoid. I had the same issue on my 07. Cheap part so might as well give it a shot!

 

Ok...my bad. I thought manual 4X4 had manual locking hubs.

 

I wish hah

 

thanks. any pointers as to what it might be if that doesn't fix it?

 

To me it seems like your solenoid is bad. Doesn't seem like a vacuum leak because your hubs are staying disengaged with vacuum. And it doesn't seem like your integrated wheel ends are stuck or leaking also because they are also holding vacuum and engaging when vacuum is releasing. To me just seems like the solenoid isn't releasing the vacuum when it's supposed to. I'd start with the solenoid.

 

so...there is a 4WD selector you turn in the cab and a manual shift lever for 4H and 4L... so.. the switch just releases the hubs.. ?? JW how this works.

 

There is no **** where the coin holder is in the manual 4x4. Manual 4x4 just has the coin holder there. There is a floor shifter for 2hi, 4hi, neutral, and 4lo. But there is still the solenoid on the firewall. So from my understanding, the floor shifter works as the "switch" like the turn dial **** to actuate the solenoid, but also gets rid of the transfer case motor and shifts the t-case manually. 4hi is still shift on the fly. But 4lo gotta stop and drop into neutral.

 

Thanks for the knowledge Boss