For my 87 26E

I have a vibration on the freeway @ 70mph LOAD ONLY. It disappears when I get off the gas...its not a rim/tire issue. I also feel like my rear end is sagging too.

I checked center support and rubber looks good, so I wanted to check rear diff mounts.

What exactly am I looking for? Anyone got any pics of a bad diff mount? I searched all over the site and cannot find much -- just a few threads.

I'm new to all the axle stuff, so it may seem like an elementary question.

Thanks guys

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