Originally Posted by RES4CUE
Because when you make contact with the stops and suspension flexes over bump like op described it is metal on metal and makes bad noises, now if you put a dab of grease on there it will lessen the friction removing the sound.
Sounds like you don't understand friction and viscosity so you call BS.
Actually the company I work for makes the OEM front lower front control (FLCA) arms for the last 5 years for the F150 and Expedition I know the product more then you might think.
Here's was like my 3rd post or so to this site so you don't think I made this up on the fly for this reply.
We are ramping up for the 2014+ 6 year program for P415 MCR (Material Cost Reduction) and then a slight engineering change for the 2015 P55X program. There is no grease put on the steering stops at the factory nor is the contact any more then a brief second when your steering wheel is turned to it's extreme right or extreme left and it is exactly what it's called a steering "stop". I can assure the cause of his noise has nothing to do with grease on the steering stops. I can safely go with BS on that one. What the other posters have said are the more likely culprits or no issue at all I just wanted to highlight that dealer gave him some questionable advice/repair. Thanks for pointing out what I do and don't know about friction and viscosity.
Here is the current generation front lower control arm in the F150 (only difference is they are black since the have the black anti-corrosion dip on it better know in the trade as E-Coat) the item circled in black is the one steering stop while the other is in the same location on the other side. Anyone who has performed any work on this will recognize this but in it's installed black color.