Most common AR is 3.43, next 3.08, very rare a a 3.73 behind that motor. I believe grit dog is pulling upwards of 10k with his work rigs. Granted equipment trailers vs an RV trailer.
Altho someone above commented on tall axle ratio, the 6 so auto has a 4.10 in first gear. So overall low is better than my C2500 with 4.10s in axel, and a supertall 2.48 in trans.
I personally would not worry about it. I've been looking at 4 3s with 3.23 in red, or 3.42 in 4wd. Not worried about it towing a 7000 lb trailer with a mini excavator.
Marty