Appropriate shocks.
Go to
www.monroe.com and step through their shock matching links to see which fits your work vehicle's expected duties. As the previous message state, any shock is better than none. I just put in thier Reflex 911055 for the front axle and decided on their Sensatrack 58591 (coil over shock) load adjusting shocks for the rear axle. In my particular case, I chose Airlift Air Springs over Monroe's Air-Max air adjustable shocks since I'll be hauling a substantial amount of weight within the bed (pickup bed camper).
If the bottom shock mount bracket holes are elongated from the shock rattling around, you'll want to take the truck in to a shop to repair the holes for the bottom bolt to have a tight fit, or do it yourself as was the case in my situation.