UPDATE: Need Your Input

Going down Old Fort,(Black Mountain), isn't that bad.....going down Saluda Grade on I26 can test one's grade braking as well as towing down I26 from NC into TN.....but using T/H and EB....have never had an issue nor had to gear down manually...(towing 5er loaded to 16,300#).

That was all the input I could think of having towed these on I40 and I26 numerous times.