My question is: would be be OK to replace my stock rear springs on my 1985 ford f150, 2WD with a heavier spring ( 3320 lbs. ) and would this effect the ride and handling of the vehicle. I plan on towing a trailer. Palmer Springs in Providence is out of stock on the stock spring and said I could use the HD spring. I am not sure if I should order the stock spring ($200 more than the HD spring) or go with a HD spring and save $200 and possible get a more stiffer ride! But, Most concern on the safety and handling of the vehicle with a HD spring?

Also, any advantage to installing the Firestone Ride Rite air bags in rear? Should I install the springs, or the Ride Rite, or both??????
Thanks
Bob