The problem with the R51 rear springs is that they are a bit weak and the rear suspension is prone to bottom out on even modest bumps. The air bags prevent the suspension from bottoming out and soften the blow, as well. Their adjustability also makes them great if you tow as they keep the back end of the Pathfinder from sagging and add another 1000 pounds of load capacity. For as inexpensive as they are and for as easy they are to install, they are a no-brainer!What benefit do the airbags do when you have HD shocks as well? Unless of course you tow. I don't want to stiffen up the rear too much.
Assuming most/all rear suspension airbags/springs are similar...they allow adjust-ability of rear ride height. This helps to keep headlights aimed properly when loaded down - whether it is cargo in the bed or trailer tongue weight. When the weight is removed, just simply air down.
For airing up: some install an onboard compressor with a controller, some use a portable tank of compressed air...I use a hi-volume bicycle pump.
There are a number of informative threads here at CF. Do a search for Ride-Rite airbags made by Firestone if you'd like to learn more. These are considered by some to be the best, most useful mod they've done to their truck...including me.
If you don't tow or haul then airbags don't help too much. If you do, it allows you to haul more than the recommended load::wink::What benefit do the airbags do when you have HD shocks as well? Unless of course you tow. I don't want to stiffen up the rear too much.
If you have a Frontier (and I understand this is a Frontier forum), that's true. If you have an R51 Pathfinder, the rear air bags make a whole world of difference, regardless of whether you tow or not. The coil springs are too weak in the rear and the rear suspension bottoms out easily. Air bags prevent that from happening.I you don't tow or haul then airbags don't help too much. If you do, it allows you to haul more than the recommended load::wink::