Leaf spring bishings shot?

So it just occurred to me...I get what I'll term a scrape-knock sound when backing out of my 30* driveway onto the street and can't find a thing that would make that noise from the rear end. Since I can't see the frame end bushing in the leaf spring its a suspect. Someone validate this for me before I unbolt the pack?

P

How long have they been on there? Have they been some tough miles?

Well they are rubber bushings, seen 2 years, they've been offroad

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Exhaust