Which chassis do you have?
My 2019, on a Freightliner chassis has not had this issue. I will say that the exhaust, during the summer on grades, heats the right front TST sensor on my toad, a Ford F150. The first time it happened, it got hot enough to trigger my heat limit alarm on the TST unit. I changed the alarm limits and solved that issue.
Later, I turned the exhaust tip, which is better described as a chrome shield from pointing down at the 6 o'clock position to about the 5 o'clock position, hoping to push the heat more out the side. When I did this, I did start to get some burning on the fiberglass surround. I turned it back to 6 o'clock and haven't had any other issues.
The toad tire still gets hot but hasn't been an issue. We just got back from a trip to Zion and Lake Crowley with the air temps through the desert at 106+.
Don & Mary
2019 Newmar Dutch Star 4018 (Freightliner)
2019 Ford Raptor