Air Shocks for 1966-67-68-69-70-71-72-73-74-75-76-77-78, Oldsmobile Toronado, and Cadillac Eldorado for assiting weak springs and for carrying heavier loads and towing. Many of our customer's tow trailers or have worn leaf springs on their classic cars and need to adjust the amount of boost: air shocks can add up to 1,100 lbs of boost per pair. Never run the shocks empty, neutral pressure is approximately 25 psi: maximum boost is at 150 psi.