I don't know about engaging any faster in manual mode? You still need to engage inside the cab. However, I have done a lot of ATVing over the years on lots of different machines and some of the systems of 4x4 engagement are definitely different. On the Polaris, if in 2x4 and engaging to 4x4 don't get stuck first. You have to have the wheels turn for the 4x4 to engage so if stuck in some big rocks or stuck in mud, you might engage the 4x4 but be spinning in 2x4. I don't believe the Ford, Chev, or Dodge need wheel turns but if coming to a situation where you think you might need 4x4, turn it on a head of time. For normal driving not so much but off road driving can be tricky. And thinking about it now, 4x4 engagement is not immediate. You hear the "Cluck" when it is engaging.

 

So that clunk is normal? Sometimes it's quite loud and I was a tad worried. If it was a Dodge or a Chevy I'd be downright frightened, lol! Its much louder than my 10 f150 was. It seems the tires do have to turn a little to engage most of the time. If engaging while stopped sometimes a drive forward message will appear and then it clunks. I usually try to be rolling slightly for best results. It doesn't always clunk but most of the time it does, maybe 1 out of 10 switches is silent. Seems to me it should be quieter but this is my first super duty, and i was figuring it was louder cause the drive train was bigger.

 

Yes 4x4 engages instantly when you have the hubs manually locked. Guys this is the beauty of our trucks. Normally if I know I will be using 4x4 in rougher terrain I get out and lock them up before hand. Then when you need 4x4 its instant as you turn the dial. However, if you do get stuck first (before locking out hubs) and can't move the vehicle enough to engage the hubs just get out and manually lock them.

HERE'S AN EXAMPLE: Last month I had a trailer behind me that was very heavy. It was dark out and I turned too quickly pulling out of an old logging road trying to turn onto the hwy. This caused my right front tire to go into a fairly deep ditch. Since you normally need to move a few feet allow the auto locking hubs to engage I was screwed. It would not go into 4x4 as the front tires could not rotate enough using auto lock. In this case a GM truck is done (LOL). So then I remembered one of the reason's I bought a F250 in the first place "manual hub option". I begin to smile and got out and locked both hubs. Got back in the truck turned the dial to 4x4 and BAM instant 4x4. Backed right out of the ditch and went on my way. Yes, its a little more trouble but man is it a lifesaver. Please don't let Ford remove the manual hubs.

I learned this the hard way as when I had the electric front locker installed I think they damaged the seal in the front left hub. I'm not sure why they would have been messing with the hub and maybe it was just bad timing but when I got my truck back I got stuck as the seal was so damaged I didn't have enough vacuum to engage the front hubs. Unfortunately, I forgot the manual hubs option which caused a friend to drive an hour to come pull me out. Later we found the damaged deal which I the same time I remembered the manual option. Boy was I pissed. Anyway good luck and hope this helps.

 

By the way, yes you will get some clunking if your drivetrain is under a load when it locks into place. Under Load is either when wheels turned on non-slippery surfaces or truck under power when engaging or both. I normally put my truck in neutral and or at least drive in straight line to reduce this shock load.

 

"I learned this the hard way as when I had the electric front locker installed I think they damaged the seal in the front left hub. I'm not sure why they would have been messing with the hub...."

Sawtooth, did they have to pull the axle shafts out to install the locker?

 

Maybe so as they fixed the issue and didn't charge me extra which tells me they felt it was their issue to resolve. At the time I didn't ask I was just glad it was fixed at no charge. The paper worked stated "Damaged vac seal" and showed replacement parts etc. Like I said in my original post I hate these new vacuum engagement systems. Yes you get a cute little girly like switch but there slow to engage, wimpy looking IMO, and very trouble prone. I would take a mechanical engagement everyday of the week. And besides there's just something more manly about grabbing a lever and snatching it back to engage 4x4. Just feels better….

Anyway as long a Ford keeps the manual option i'll be happy.

 

I like them fully manual myself. On my '99 F-350, I ordered it with a manual transfer case and manual hubs (I don't remember if I actually had a choice in what hubs came on it). In my '97 F-150, I had the manual lever for the transfer case, but was stuck with the vacuum actuated hubs and lost one while doing "light" off-roading when a stick pulled the vacuum line off of one hub. I like the fact that these new ones at least allow me the choice.
As far as having to get out and lock my hubs on my '99, I never saw that as a big deal as I never found myself "suddenly" in a 4x4 situation. I always knew ahead of time that the potential was right around the bend, so I would lock my hubs before I needed 4x4, then engage the transfer case with a solid tug when it was needed. I never got muddy boots from having to lock hubs - even though they were strictly manual.

 

I had a similar situation as you. My question is this: If the hubs are in auto, 4x2 selected, 30 mph on a dirt road, the front drive shaft, differential and axles are idle (not spinning). When 4x4H is selected while doing 30 mph, what brings the considerable mass of the front drive train up to speed in order to synchronize the transfer case gears to engage the front drive shaft and the wheels with the axles? Is there a clutch somewhere and, if so, what operates that clutch? Vacuum? Since no warnings were in the owner's manual, I have done this before at about 15 or 20 mph and no 'clunk' with the front end engagement so the machinery must be synchronized. Normally, I try to drive ahead of myself and when I think 4x4H will be prudent, I select it on a straight run 50 yards before the need.

All this driving and synchronizing talk should get my SeaBee EO friends out there excited!

 

I'm sure the systems are durable, or they wouldn't recommend switching while moving, but I've always engaged only when moving slowly or stopped. I guess the thought of all of that mass suddenly turning up to speed from a dead stop and engaging gears has me thinking that somehow it can't be a good thing.

 

"All this driving and synchronizing talk should get my SeaBee EO friends out there excited!"

In the Bees, I never concerned myself too much about things like this. The EO's break them and the CM's fix them. Now that it's my money and inconvenience, I'm more cautious. Even if something is designed to handle certain situations/conditions, it does not necessarily make it a good idea. I was fun finding the limits of military equipment though! Can Do!

 

"The EO's break them and the CM's fix them."

Things were not so dramatic in the UT turd chasing arena.

 

There were some pretty derogatory remarks made about UT's back in the day. I didn't want to got there!

 

Its already all turning it just isn't locked together. You can shift into 4x4 at any speed. You just don't want the front and rear tires to be going different speeds. That's why going straight coasting with your foot off of the accelerator and brake is the best method.

 

I thought the purpose of having the hubs unlocked was to NOT have all that stuff turning all the time, thereby saving fuel and wear and tear. I know I have seen the axle shafts on the fronts of other trucks with unlockable hubs not moving while the vehicle is in motion. (I could see the u-joints in the knuckles stationary.) Granted, as previously stated, this is my first experience with these newer style hubs.

 

Maybe I'm wrong, I don't know all the tech specs but ive regularly engaged it going 60-70 in my f150 and it didn't clunk. Maybe the super dutys are different but I've done it at 40 and it didn't clunk any more than if I was going 3mph. I haven't read the manual, hah!