Whats the trailer tongue weight?
Whats make model of trailer?
Your probably at the 6 k level of hitch 90-00-0600
But I would maybe go with the 10K...90-00-1000 This have the 1000 lb bars...
Your right on the cusp...
But then again you trucks suspension is adequate for the 6k..
If you had a weaker smaller truck suspension like I have go with 10K..
I have the 10k and pull 4500-5000 wet... With my s10..