I also purchased and assembled the Rock Tamer, but haven't used it yet (my trailer build is in the works). After getting the Rock Tamer put together, I started questioning whether the rear exhaust pipe on my vehicle would pose a problem. When I read your comments about this issue I pulled out the assembly/instruction manual that came with my Rock Tamer and (sure enough) I found one teeny tiny sentence about this: "Vehicles with exhaust systems that cannot be modified should maintain at least 10 inches between Mudflap and exhaust". To me, the key word is "should". There is no mention whatsoever though that not heeding this miniscule recommendation will lead to a hole in the mud flap.
I see that Kent mentioned changing the exhaust tip to divert the heat downwards and Evan mentioned doing his own modification. I don't have the know-how to do such a modification myself. I'm guessing a muffler shop would be able to change the exhaust tip (but I haven't looked into it yet). More to the point, I'd rather not do this at all if it isn't necessary. I need to check the space on mine, but I seem to remember there being about 4 or 5" of space between the exhaust and the mud flap. Anyhow, I'm wondering if there is a general consensus out there as to whether it is necessary to make such an adjustment on a rear exhaust vehicle. Has anyone ever known rear exhaust pipes to actually burn a hole into these mud flaps?
Kelly