Intermittent rub in rear suspension

04 Tacoma 4x4 TRD Xtracab. Developed an intermittent rub during my last outing in the desert. Sounds like it's coming from the right rear shock. Only happens when you're going over something that makes the rear suspension articulate asymmetrically (left up/right down, vice versa) and it's really brief, only over a short portion of the travel. Doesn't happen during normal driving or hitting a bump head on. No visible signs of wear. Stealership didn't see anything wrong either. Anyone have anything like this in the past? Thinking about just swapping out the rear shocks and seeing what happens. Thanks

 

possibly the leaf spring is rubbing on the shock body...
inspect the leaf side of the shock's body for abrasion or dents.

I extended my Rr. shock mount(s) inboard farther
for this very same reason.