What Are You Doing To/With Your Car Today?
Feed grade molasses. $10 for 1 gallon at tractor supply co. They use it to bait for deer and wild hogs. Once its starts fermenting and getting real nasty after a day or 2 dont get it on your skin as it will take days for the stench to wear off your skin. I'm liking this stuff better n sandblasting. Gonna get a tub big enough for dipping steel wheels, and K frames. Economies of scale $30 will get you 30 gallons once you dilute it with tap water.
Powdered Tri sodium phosphate at lowes in the paint section. A small box about $4 mix 1/4 cup in solution to about a gallon of water. Use as a rinse solution. When you pull the part from the molasses, rinse right away with the TSP and water if you let the part dry before rinsing it will start to flash rust. Once you rinse it off, let it air dry. You should be able to primer it as soon as it dries without wiping down with any paint prep solvents.
Sometimes with heavily pitted areas, i will lift the part out of the tank, after the first few days, and scrub the affected areas with a steel wire brush, rinse, inspect to see whats left rust wise, then lower back in the "primordial ooze" for another day or so until the rust is gone.