Spraying fluid film under my 2007 EL Eddie Bauer today and was looking at this and the question begs.....center differential or transfer case? We have 2H, 4A, 4H, 4L, so it has two speed gearing. But in all definitions clutch packs are also mentioned. I have also read it’s chain driven as well...so what the heck is it? I have done a lot of reading on the ControlTrac 4WD in our 2007-2014 Expeditions. It has a microprocessor (computer) of it’s own which can send and direct torque wherever needed and often times can predict slippage before it occurs in the first place. Has two speeds, clutch packs, chain......is it a hybrid of sorts? I’ve always called it a transfer case...