What is the standard procedure for going into 4HI? I thought that this could be switched while driving? When I shift from 2WD to 4HI it doesn't engage until I come to a stop. Is this normal? My 4WD seems to work fine and I have no issues getting it out of 4WD, I just have to be stopped.

 

4hi should not require you to be stopped. Anything up to about 55mph is good. This is all listed in the owners manual.
What makes you think that it is not going into 4hi when you shift while moving?

 

Right, - If it's SOTF. The 7700's were not, some 4.6L's weren't as well. All the regular duty 5.4L's were. I shift on the fly while on the expressway all the time, never a problem with the system. My lines cracked once, but I caught that before needing 4wd. You HAVE TO maintenance the actuator. That's the #1 reason why these trucks end up at the dealer with the 4wd not working. How you do that, - hose down the actuator pin w/lubricant and with a vac tool, operate the actuator to 4wd then 2wd modes. That's usually all they have to do at service to get them working again.

 

Also, most fluid service changes in T-Case, the fluid looked like swamp water. It only holds a quart I believe and the fluid breaks down fairly quick compared to the trans.

 

Transfer case takes 4 pints (2 quarts) of ATF.

 

That sounds better, - I new it wasn't much.

 

Just checked the 2002 OM. It gives no distinction between any of the different versions. 4hi can be shifted into, whether MSDOF or ESOF or any model or engine, at speeds up to 55. Only limit is if the temp is below freezing, then not above 45. No other limitations.

 

That's right, I was mistaken. Even tho everything is on the floor, you can still go in and out of 4 high in motion. Not sure why I said that, I know this duh... My coffee's still in the cup, that may be a contributing factor.

I'm not doing very well in this one .

 

That's okay, we all have bad days. My last one was in 2011, unfortunately it is still happening..