Need some help. Got a new boat approx 6500# +. I know its close to the weight limit. Put a 6" lift on the ball and it still sank 2 1/2 inches down (pulls itgreat!). Need to level it out.

But whats the thought on a helper-spring , air bag or just add a leaf. To help raise it up so the back doesn't sag so much.

 

I would install airbags. They are more expensive but its worth it as you can adjust your ride with the boat hitched, and then set it back to normal when you unhitch. Airlift has some slick stuff out now. They have a system that will "auto-level" your truck when you hook the trailer, or put a load in the back. Not gonna get that with a helper spring.

 

I'm no truck genius by a long shot. Just a truck user. I'm an electrician for an entertainment power company. We tow generators ranging from 6000 pounds to 28,000 pounds (with various trucks). I'll load the beds with switchgear and cabling. So, you can see our loads vary quite a bit. Heavy, Light, Lopsided, Stiff, Sloppy, etc. I'm also often traveling empty when the gear arrives by plane. I always try to get a truck with air springs when I'm using a fleet truck. My own personal Sierra has Air Lift 5000's. The helper springs can't really be "turned off", nor can an out of balance load be corrected left-to-right for level. When I had those and was empty or lopsided, I went nuts. (Sometimes, I stuck up so high in the read, my ABS system protested. There were McDonalds french fries everywhere! Forget about a cup of pop. Another advantage to air is that you can always be level. This is critical for a safe tow, especially on ice. (It doesn't hurt to pass a weighmaster level, either.) Another benefit is the tires don't skip around so cornering is easier.

For my truck, I simply adjust the pressure from 5 psi (the minimum to protect the bags) to as much as I need to keep level. I'm in the process of building an on-board compressor system with a converted garage door remote to operate fill-empty. This way I can fine tune it while driving as well as from the rear end to check front to rear and left to right leveling. (They make great ones, but buying one is no fun.) To fill mine now, I carry a $10.00 12 volt compressor, rigged to a 6 pin trailer socket. I put my air schraders (fill valves) into my license plate screw locations. Looks stupid, but no holes in my bumper.

I hate to sound like a salesman, but these air Lifts are great. It took me about 3 hours to install my set and I've done some for friends and it is a 1 hour job. I drilled nothing and didn't even have to raise the truck or remove the wheels. (A couple of pointers are: Start soaking the jounce bumper fasteners with penetrating oil a few days ahead. These come off for the install. Measure a new truck like yours for wheel well opening to wheel center. This way, you can always be at factory pitch no matter what the tongue weight is. Your aerodynamics, suspension, ABS and more will be proper.)

In summary: I really like these springs!