hetman

when in 4 hi :


ELD Locked in - do you have 3 tires pulling @ same time(2 rear & @ least 1 front)


ELD not locked - just 1 tire front & rear pulling at any given time ?




4hi /ELD unlocked - is there any reason you can't lock 4hi @ high speed 60-70mph


I had a 07 150 4x4 & running 60-70- hit a bad rainstorm / we could lock 4hi @ speed and keep on trucking. hopefully the new series F150 work the same way.




**sales dept. @ dealership told me 4x4 works : 2 front pulling & 1 rear &
w/ELD engaged all 4 wheels are locked and pulling**


( neither statement sounds right to me)


Thanks Het

nickel_work87

When you have the eld locked yet locks on the rear wheels until 25 mph then the computer unlocks it to prevent damage. You
Have a open diff in the front so only one wheel will spin up there. I believe that you have to stop to go in to 4hi transfer case has to lock in. Plus I would not go that fast in 4hi on pavement.

king nothing

You shouldn't have told stop to shift to 4-high. 4wd trucks have had shift on the fly t-cases for decades. If I could shift my 79 bronco while moving I can't imagine my 2013 wouldn't have that capability. I probably wouldn't do it at 70 but 55 wouldn't bother me a bit. Of course if weather dictates that you need 4wd you probably shouldn't be running 65 or 70 anyway

SuperCruzin

with traction at all 4 tires, in 4 high, power is going to 4 wheels. If 1 tire has no traction and slips, the energy is wasted out the side slipping. if there is no resistance, there is no torque transferred to the opposing wheel on the same axle. Yes, only 1 wheel will "spin", but both are still powered... Unless you have LSD or locker (ELD) of some kind to redirect torque and force the other wheel to turn, then both will, but still only 1 on the opposing axle, unless it too is equipped. This goes for both front and rear axles. If you are only engaging 1 axle and no ELD or Locker is present there is the possibility of only 1 wheel slipping and you not moving. A LS diff will lessen this risk, but it is still possible to defeat it.

Yes it will go in and out of 4x4 at highway speeds... on the fly, in about a second or so if I had to guess.

driver444

2 things to add.


1.Yes the ELD will unlock in 4hi at 25 mph, but I believe it stays locked at any speed in 4 low. Ford probably does this because a fully locked rear diff can cause adverse and unpredictable handling issues at speed, (especially on slippery roads), and nobody's going to use 4low on the highway.


2. You can shift into 4wd high at any speed up to 50 or 55 mph (according to the owners manual), In our trucks, when you shift into 4wd, the transfer case and front drive shaft has to "catch up" to your road speed before it locks in your hubs. The faster you're going when you shift into 4wd, the more "catching up" it has to do. So even though you "CAN" do this, I'd recommend doing it at a much lower speed or totally stopped.


(sorry, 3 things)


3. If you every want a straight, correct, accurate answer on how anything in these trucks work... NEVER NEVER ask the sales department!!!

SuperCruzin

Ok, so 55. I don't ever recall seeing that warning, but its usually in 4x4 long before that speed anyways... Once locked into 4x4, it does stay there right? I'm 98% sure it does. I don't ever recall mine kicking it out.

^ this is the truth. They will tell you ANYTHING.

EDIT:
Oh, and thanks for the info about the ELD and 4 low. I never really messed with 4 low at any kind of speed.

Raven2210

The owners manual spells all of this out and that 4x4 high can be engaged at any speed. I realize this site is intended to get valuable info out to everyone. But I always always always refer to my manual first, before posting.

Thislilfishy

Is the front diff open? It really feels like a LSD diff, as they really don't turn well on dry pavement in 4x4.

Ian

SuperCruzin

yes it is open.

In a turn, the front and rear axles travel on a different arc. The binding you feel is a result of that phenomenon and not having a center diff to equal it all out.

Thislilfishy

Aha! That makes perfect sense.

Ian