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Crasher

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I'm having my 249 swapped for a 242 this week. I just noticed as I shifted it through the positions that in full time 4wd when I turn the input shaft and hold the front drive shaft, the rear one turns and when I hold the rear shaft, the front will turn. How is this full time? Should it be called either front or rear drive? Does it respond differently if with all 4 tires on the ground or put the power to the least resistance?
 
Full-time is a 40/60 split between the front and rear. It will react differently under load of the engine. I doubt you put it together wrong. Slap it in.
 
You need to understand the mechanics of the 242 "Full-Time" position. "Full Time" not meaning it is there all the time, but meaning that you can drive in that position ANYTIME you want, wet or dry, paved or dirt. The full-time position gives you some mechanical "slip" much like in a diff. In the 249 this is done with a Viscous Couler sort of like a torque converter for a weak analogy. Where as your 242 the full-time position really is a mechanic diff. So the path with the least amount of traction gets the power with a slight bias towards the rear,

Not to pick a fight but the last of the ZJ' and the first few of the WJ's the sales material said, and 48/52 power split. I know as I had the the opportunity to be shopping new back then, not any more unfortunately. I believe it was that way most of the way thru but that I'm not nearly as certain about.

So anyway, when you spin one you very well might not spin the other at all while off the ground and spinning by hand. This is why when the going gets really tough most guys with a 242 start shifting into part-time high or low. Part-Time is the Lock and Load, both shafts are locked together spinning at the same rate with no mechanical slip to be had. That is why you don't drive a part time rig on hard paved roads until there is enough snow or ice to act as the slip...

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i'll second the power goes to the least resistance idea. I've been in full time 4WD facing uphill with both front tires on ice (rears have traction), and been unable to move forward... the front wheels just spun while the rears did nothing. Pop it in part time, it locks the shafts together and the rear pushes you over.
 
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