i'll start this off by saying that i owned n '09 ranger sport 4x4 and a 2011 dodge 1500 big horn 4x4, now i'm currently running a 2013 f150 fx4 and according to ford techs it has the worst 4x4 on the fly i have ever owned. but let me step back here for a second, it all started when i was driving out ov a parking lot one day and i thought to myself i haven't used the 4x4 hi yet so i turned the **** and i here a loud banging noise and the truck kind of lurched a bit, so i was more then a little concerned do to the fact that neither my ranger or dodge had done this. so i go into the dealer and do a test drive with a mechanic and his reason for this was that, because i was accelerating it slammed into gear roughly, and he also informed me that the f150 4x4 will turn off past 100kmh, he also said that in order to enable 4x4 high i would have to be sitting still. now this really gave me oause on the capability of the truck if i cant have my 4x4 available if i need it at a seconds notice. so is this tech just blowing hot air to get out of a length diagnostic and fix or is this really the capability of the f150 4x4 system?

 

He is blowing hot air...you can shift on the fly into 4H at any speed below 55MPH...but you do not want to be on the gas while doing this...just maintain steady speed..to get into 4L yes you have to come to a complete stop and shift into "N" before your truck will engage 4L...

 

The 4x4 mode can be engaged while moving up to 50 mph. I don't know where that mechanic got his info! I always back off the throttle while engaging the 4x4 though, just to take it easy in the transfer case and transmission, but I'm still moving of course.

 

You really should open the owners manual and see what it says about your 4X4 system and controls.
You don't say whether the parking lot was dry or wet but very important: "4WD should never be operated on dry pavement".
There are some other items there that should be helpful to you also.

 

Ditto!

 

yes the parking lot was dry as is most of the pavement i use my 4x4 on i normally use it during the winter, and what about his other statement that at 100kmh or 60 mph the 4x4 will automatically disengage.

 

4 wheel drive shouldn't be used on dry pavement. snowy roads are ok.

 

As stated above, read the owners manual. 4X4 is not intended for dry pavement. Snow covered or slick roads it is fine. This is not an AWD system. Some people confuse the two. AWD can be used full time. Use it as stated in the owners manual and you shouldn't have problems. It is a very good system when used for its intended purpose, improving traction on slick surfaces. And why one earth would you need to be in 4X4 at 100 kmh?

 

I do not believe that it disengages automatically, tech was probably confused in that you should not ENGAGE it while travelling at that speed.

I think the bigger question is why one would be travelling that fast in winter conditions that make you want to be in 4WD in the first place...if conditions are bad enough that you need 4wd, you probably ought not be going that fast in the first place.

 

I have a spot by the house that I go out to all the time for trails and a little mud after a good rain storm. There is a paved road that hits a dirt road / path, and I do not slow down or stop once I hit it. As soon as I am on the dirt I let off the throttle for a second switch over to 4 hi and lock my axle if it looks really bad.

I would agree with all of the above posts! No dry pavement, and do the un-manly thing and read the instructions!