99 K2500 Burb overload springs

[MalibuSSwagon]

Anyone put overload leaf or heavier springs on their 3/4 ton Suburban? I have a 99 K2500 Suburban 454 that I use primarily for towing a car trailer, when I have 5-6k pounds on it, (trailer+towed car) the truck does sag quite a bit. I'm planning to purchase a new 10k trailer in the coming months to haul more trucks home, my worry is that the Suburban, which is meant to be a luxury family hauler, does not have enough spring in the rear for that weight despite its 10k tow rating. I also have an equalizer hitch for a 10k trailer which I will employ. I don't want to go to a dually pickup as I like having the clean dry storage for all my tools and equipment.

Thoughts on my rambling?