I apologize gentlemen, you are all correct. I some times don't think before I just start typing away, I do that way to often.
I know we have IWEs and they are vacuum activated.
I had my 84 full size Bronco in mind. I always wanted to put lockers in the front to get a true 4 wheel drive.
Truck rusted out before I do anything with that. LOL
In any case I was told by a few techs that in 2011 Ford changed something in the Raptors IWE, what I don't know.
They also changed the rear with bigger parts, pinion, shafts, bearings. I just wonder what they did to the IWE?
And I did not realize (or forgot) they started in 2012 with the front locking diff.
Now, why was I told that I wouldn't have a problem launching in 4x4 in my 2010 1/2, even with 560 rwhp when it comes to the IWE,
transfer case I will wear out faster especially the chain.
I have been doing 4x4 launches for over three and a half years probable over 200 if not more.
I get the two rear and front divers side to spin for a second or two when taking off.
I mean that has to be harder on the IWE then pulling a tree stump, unless the wheels were turned.
I only do straight line take offs and I make sure I roll forward a bit!!! to lock everything, that's a habit I've been doing for all my 4x4s.
So far knock on wood I haven't had an issue.