Drive Shaft spins as if the rear differential is slipping

[chefjoey29]

At certain times the drive shaft spins freely when my 1967 Ford F-100 is in gear. It will not move forward and tends to "jerk" into gear when I first start driving it. It seems as if the gears in the rear differential must be damaged, but I am not sure where to start. I am also concerned that if the rack and pinion are damaged, the gears on the axles might be as well. I do not have much information on the truck as I have only owned it for a short time and have no history on it. Has anyone experienced this problem before?

[70shortwide]

you say it happens sometimes? does it happen as you go around corners? broken spider gears will cause funky stuff to happen when you turn. causes them to turn a little bit and get on a good part of the gear (or a bad part, which could cause the freespin) In my experience it is accompanied by lots of noise. snapping and popping.

[HIO Silver]

At certain times the drive shaft spins freely when my 1967 Ford F-100 is in gear. It will not move forward and tends to "jerk" into gear when I first start driving it. It seems as if the gears in the rear differential must be damaged, but I am not sure where to start. I am also concerned that if the rack and pinion are damaged, the gears on the axles might be as well. I do not have much information on the truck as I have only owned it for a short time and have no history on it. Has anyone experienced this problem before?

'Rack and pinion'? ... you must be referring to 'ring and pinion'.

[tac]

This could also be a broken axle.

[fordman]

In order to remove the ring and pinion center chunk. U will have to remove drieshaft and axles. Inspect each piece as u remove it. U will find the bad or worn part as u disassemble. If it was the two piece driveshaft only half woyld turn while the back half wouldnt. If it stops u at low speeds the carrier bearing is going out. Also read above comments they r true also.