Generally, rear axle end play on a tapered axle shaft like the Dana44 is measured in thousands of an inch. A properly setup D44 would measure from .001-.007".
However, I would pull the shafts and check everything out or have someone do it. If you choose to do it yourself, pay attention to tightness of flange bolts, condition of seal, scoring of races, amount/quality of bearing grease, visibly wore parts etc.