While driving at highway speed my 2007 F150 has engaged in 4WD. When I slow and come to a stop it shifts out quite loudly. This model has the electronic shift switch. When this happened I had not attempted to shift in to 4WD High. Any others seen this problem??

 

You have a vacuum leak in one or more of your lines. Or your IWE solenoid is bad.

 

Thanks Charger.... It is very disturbing when it happens.

 

I bet. your vacuum drops when your RPMs climb, so that would explain why it's doing it at highway speeds. It's probably getting ready to, or trying even when you're taching higher in the city too. If it's both front wheels engaging, I'd start at the IWE solenoid and work my way down. Shouldn't be too hard to find.

 

Chargers Fan, so your saying that it's not actualy going into 4 wheel drive but the front hubs are locking up?

 

Yeah thats whats happening, its your IWE solenoid going bad, a leak in the hose or your actuator in the hub is going bad. I had to replace both on my 05 at around 44,000 miles. The work is easy to do your self too if thats your problem.