Real wheel wobble

[Dswood1]

Just purchased a 1984 manual transmission Ford ranger pick up with the 6 cyl engine. When parked and in neutral you can grab both rear wheels and they have a pretty good wobble when you shake them. The left rear wheel has almost new tires on it with some unusual wear on the outer edge although the right tire seems fine. First general mechanic we took it to wasn’t concerned with what I call ‘slop’. It’s my sons first vehicle he purchased and this is the only concern that I have. Not sure if I can upload a video to this thread? That might be the only way to convey what we are seeing and feeling

 

[Curious Hound]

Video needs to be hosted elsewhere (YouTube is easy) Then you put a link here.

About the only thing I can think that would cause "wobble" on the rear wheels would be loose lug nuts or bent rims or axle shafts.

However. If you're talking about being able to move the wheels straight in and out toward or away from the differential, then a small amount of play is normal. On the Ford 7.5" and 8.8" axles, the shafts are splined to the side gears in the differential and held in place by a C-clip in the differential. There is normally some play between the inner end of the axle and the cross pin in the differential carrier. I don't remember the spec. But I wouldn't be concerned with up to 1/8" inch of play on each side. This play should not cause abnormal tire wear.

Pictures and/or video would be helpful.

 

[Curious Hound]

One other thought. Did you put new tires in the truck? Or did the previous owner? Is it possible that the tire wear occurred on the front of the truck and then the worn tire got moved to the rear during a tire rotation?