The nice thing about the coilovers is they are probably adjustable. A drawback is they can make some noise.
I’ve had aux air bags and learned a few things. They must always have 5 psi in them to prevent collapse. The Firestone ride rite bags are about 4-5” diameter, and 5 psi in those in an unloaded bed is enough to break your teeth over speed bumps, or they were in my tundra TRD. 25psi in them with a 6000lb trailer was wonderful. There is another brand which is more like 2.5” diameter. They allowed the suspension to work more at the unloaded, 5 psi situation, while still providing lift under load, albeit at higher pressures. a friend of mine had a set and really liked them.
i tempered the ride rite bags by installing larger diameter pipe to an accumulator over the rear axle. When all that worked and it didn’t leak, it was great. Mine leaked some. I added onboard air, using a cheap compressor and valves off Amazon and a low psi boost gauge. When it worked, it was great. It leaked more, but I used it until we sold the truck. Again, simpler is better.
my recommendation - buy the kit with the smaller diameter bags and the onboard pump with in-dash gauge and set points.
also, No leveling kits.
also, anything you can fix with weight distributing hitch is far better than air bags. All that tongue weight unloads the front wheels and messes with steering and braking. If I could do it all over again, I would have avoided air bags altogether and improved the WDH.
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