so while on steep hills i was haveing a loud grinding noise from the front of the jeep
we thought it was the motor at first but only does it on steep hills in 2 or 4 wheel i think
i had all 4 tires jacked up and ran it in 4wheel with the brakes on and no noise and front has power
today i noticed i can turn the tires and while in 4 wheel or holding the front drive shaft only the spidergears turn! and the tires turn freely,
does this mean its broken whats broken?

 

Pull the cover and take a look.

 

already did theres nothing too look at.
i need to know the last question
i can spin the tires in gear and the pinion gear doesnt spin. is it supposed to free spool the way its doing if i turn the drive shaft then it does spin and give power to the front wheels, but something is broke and grinds when under heavy load

 

Yes that is normal. If the driveshaft can not turn you are jus tspinning the spider gears. If you hold one tire you should not be able to turn the other one.

 

If the tires are spinning opposite of each other when the pinion is not turning that is normal. If only 1 tire spins and the other does not while the Pinion is not turning you have a problem.

Max