odd rear diff question

[bored808]

I had 2 complete rear diffs sitting on jack stands in my driveway. One was a 3.55 and the pinion spun real easily. The other was a 4.10 that only spun if I put a pry bar in the yoke instead of the u-joint. I owned a ranger with 4.10 which I installed and it spun nicely.
Am I smoking crack or is there something wrong with that 4.10 rear for my F350? Yes the brakes were off both f350 rears.

[cdnsarguy]

Suggest popping the cover and checking.....could be full of water?????? or whatever. Bad pinion bearing would do the same..... Do the wheels turn, are they both LS or open axles.

[Mr_Roboto]

I'm going to say something is wrong with the 4.10 axle. I just pulled a F350 axle on a truck that has been sitting for more than 5 years, and it turned easily.