FOX runs a 550 lbs/in x 16.73" (3.680" ID) in their aftermarket kit. Spring rates would be very similar to that of the factory.
What you are experiencing is a result of the spring; You have an SCAB and the rate is high...and also super short. Perhaps the rate is a tad more suited for the SuperCrew but still high in my opinion...As far as valving/rebuilding. Definitely worth revalving if moving into a new spring rate/length, and rebuilding them would be dependent on the mileage they have. If uncertain, having someone rebuild them would offer you the peace of mind and good for another 50k+.
With a little effort you can improve the ride with the Sway Aways. Or consider stepping up into a FOX or KING for the path of least resistance.
