we all have heard about dropping the front drive shaft on a four wheel drive vehicle with that being a fact why couldn't one drop the rear drive shaft and use it as a front wheel drive?

 

Less efficient.

 

because you would have to engage 4 wheel drive and depending on what TC you have if its 231 you have part time meaning you shouldn't use it on dry pavement. i believe the 242 has the full and part time where you can use it on dry pavement with full time. ever been in 4W and turn real sharp and it jerks your steering wheel and such. that's why.