This is my first bit of research regarding this issue. I have a 2007 F150 5.4 Fx4. For a couple of weeks, I have noticed and been paying attention to a slight whining sound from the engine with no other symptoms. I have now in the past day or two started to experience some change in my power steering performance. I still have power steering and don't notice too much difference in normal driving but at slower speeds and tighter turning radii, as in manoeuvring in a parking lot, there is a bit of resistance or lack of consistency in wheel feedback. The fluid level is correct. What things should I look at to zero in on the exact cause for this? Thanks for any help.

 

I wonder if one or both of the front 4X4 hubs could be stuck in the engaged position?

 

I know what that feels like and I don't think so. Because of the new noise which seems to be coming from the engine and the feel, I don't think it is the hubs. I do engage 4X almost daily for short off road driving and this truck is exposed to muddy conditions. It is something I had not considered and will look at though. Thanks for the suggestion.

 

Newcoyote do you feel the stiffnesss in the wheel while in 4wd at low speeds? If not I would for sure suspect an iwe accuator is stuck in the open position locking the hub. As Montana mark said..

 

Mine was also bad and it sounded and felt like a tiny engine brake was trying to activate

 

The only time I have noticed is on hard surfaces in 2WD. Anytime it is in 4WD there are other obvious variables at play i.e. mud and uneven surfaces. Not that it occurred to me as of yet. Are you talking about the vacuum/solenoid on the firewall? That would be easy to check and rule out but the one on my truck is only a couple of years old and the retrofit version.

 

Understood .. probably hard to tell while on tough terrain.. the vacuum solenoid could go bad causing what sounds like your problem, but most likely not since the retro fitted one with the umbrella is on it.. then check for vacuum in the lines going from the solenoid to the iwe's / hubs.. which is probably also not the problem.. I'm reffering to the iwe accuator that locks into the hubs when there is no vacuum enabling 4wd.. jack the front of truck up and the wheels and split shaft axel should spin together..turn the truck ON in 2wd and the wheels should freespin without the shaft turning..if the wheels don't freespin when truck is on in 2wd..then there's ur problem..

 

Right. I'm somewhat familiar with the IWE system and how to confirm/rule out. I still don't get the feeling this is the issue but feeling is not enough to ignore what sounds like a plausible problem and has been suggested by more than one person here. I will definitely be including it in the diagnosis process now. It probably would not have come up in my head this soon. That's why I always ask for others ideas.

 

gd luck let us know what the diagnosis was ..it could be my next problem!