The Norwesco 500 Gallon Applicator Saddle Tank (N-40274) is a white polyethylene tank built for pull-behind fertilizer and liquid applicator rigs, where a low, saddle-shaped profile keeps the load stable over uneven ground. It holds 500 gallons, carries a 1.5 specific gravity rating, and measures 75" long by 48" wide by 51" high with a 48" x 75" footprint. Empty weight is 121 lb, the tank uses an 8" lid and a 1.25" outlet, and it is rated to a maximum contents temperature of 120 F / 48 C. Norwesco lists it with FDA-approved resin. If you are shopping applicator, saddle, or 500 gallon Norwesco tanks, this is the standard fit.
Will it work for your load
Match the tank to the weight it will actually carry, not just the gallons. Full of water (SG 1.0), a 500-gallon load runs about 4,170 lb. At the tank's 1.5 SG rating, maximum rated contents weight is 6,255 lb — so any liquid up to a specific gravity of 1.5 is within rating, and heavier liquids are not. Confirm the SG of your blend before you fill; a dense fertilizer solution eats into that headroom fast. Run your product and volume through the Tank Sizing Calculator and the Tank Sizing Guide if you want the weight math done for you. For plumbing the 1.25" outlet and the trailer setup, our guides on Norwesco applicator and leg tanks for fertilizer and the 49 CFR 173.5 agricultural exemption cover the DOT and non-roadable-trailer questions that come up on farm fleets.
Chemical compatibility
This is a polyethylene tank with a 1.5 specific gravity rating. The resin type — HDLPE versus XLPE — is not confirmed in our source data, and the two have different resistance profiles, so verify it with Norwesco before any chemical service. Compatibility is also concentration- and temperature-specific: check your exact chemical, concentration, temperature, and fitting plus gasket materials against the Snyder Industries OEM chemical resistance chart. Within the 1.5 SG rating, this tank suits Acetic Acid (60%), Aluminum Sulfate (50%), Calcium Chloride (40%), DEF (32.5%), Ferrous Sulfate (20%), Magnesium Chloride (30%), Sodium Carbonate (30%), Urea Solution (50%), and Ozonated Water (up to 10 PPM), most calling for PVC or PP fittings with EPDM gaskets. For the two ag products most likely on a saddle applicator, DEF (32.5%) and Urea Solution (50%) both clear at a 1.35 SG requirement — well inside this tank's 1.5 rating — but DEF requires 316 stainless fittings, not the PVC/PP used elsewhere.
The mistake to avoid
Several common applicator chemicals need a heavier tank than this one. Ethylene Glycol, Ferric Chloride, Hydrochloric Acid (37%), Phosphoric Acid (85%), Sulfuric Acid (98%), Hydrogen Peroxide (50%), Sodium Hypochlorite, and Peracetic Acid all require a 1.9 specific-gravity-rated tank — do not run them in this one. Call 866-418-1777 and we will match you to a heavier-rated Norwesco for that service. Note too that several of these also require Viton or Aflas gaskets rather than the EPDM used for the compatible list — the gasket is as load-bearing as the tank rating, and EPDM on a Viton-spec chemical fails at the fitting even with the right tank. Start at our chemical compatibility resource to check your product before you buy.
Freight
This tank ships LTL, quoted live to your ZIP. Norwesco produces from plants in Burnet TX, Fairfield TX, Griffin GA, Hanford CA, Lancaster OH, Owego NY, Shawnee OK, Sheldon IA, St. Bonifacius MN, Tooele UT, and Washougal WA — freight ships from the plant nearest you, which keeps cost down. Get a real number with the Freight Cost Estimator, or call us at 866-418-1777 and we will line up the tank and the freight together.
