The Norwesco 400 Gallon Plastic Applicator Saddle Tank (N-40137) is a specialty applicator tank built for fertilizer and liquid-chemical hauling on an implement or applicator frame. It holds 400 gallons in white FDA-approved polyethylene, weighs 101 lb empty, and carries a 1.5 specific-gravity rating - the number that decides whether a given liquid is safe to run in this tank. The saddle profile drops the load low and stable over a footprint of 42.0 x 74.0 inches (45 in tall), with a 1.25" outlet and an 8" lid for filling and inspection.
Will it handle your load?
Sizing by weight matters more than gallons here. Filled with plain water, 400 gallons weighs about 3,336 lb. At the tank's full 1.5 SG rating, the maximum rated contents weight is roughly 5,004 lb - and since the tank itself is only 101 lb empty, that means nearly 4,900 lb of liquid riding on your implement frame and saddle straps. Confirm the frame, saddle mounts, and any trailer are rated for that full 5,004 lb before you fill. The 1.5 SG rating means any liquid up to 1.5 times the density of water is within the tank's design; heavier liquids need a higher-SG tank. Max service temperature is 120 F / 48 C. Run the numbers on the Tank Sizing Calculator and the Tank Sizing Guide before you commit a load. Ports are a 1.25" outlet and an 8" fill and inspection lid; fittings and valves are not included and should be specced separately to your chemical.
Chemical compatibility
This is a polyethylene tank (resin listed as HDLPE) rated to 1.5 SG. The resin code carries a "?" - confirm HDLPE versus XLPE with us before any chemical service, since crosslinked and high-density linear polyethylene differ in chemical resistance. Per the Snyder Industries OEM chemical resistance chart (concentration- and temperature-specific), liquids compatible with a 1.5 SG polyethylene tank include 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 call for PVC or PP fittings with EPDM gaskets; DEF wants 316SS fittings with EPDM. Some liquids you might expect to haul are NOT safe in a 1.5 SG tank and need a higher-SG build - for example Sulfuric Acid (98%), Hydrochloric Acid (37%), Phosphoric Acid (85%), Sodium Hypochlorite (under 16.5%), Potassium Hydroxide (saturated), Ferric Chloride (50%), and Ethylene Glycol all require a 1.9 SG tank. Note that these aggressive acids and oxidizers do not run on EPDM - Sulfuric, Hydrochloric, Phosphoric, Sodium Hypochlorite, and Ferric Chloride all call for Viton gaskets (Peracetic Acid needs Aflas), so do not reuse an EPDM-gasketed fitting when you move up to the heavier tank. Always verify your exact chemical, concentration, temperature, and fitting plus gasket materials against the chemical compatibility chart before service.
The mistake to avoid
Do not size this tank by gallons alone or assume "plastic tank = any chemical." The 1.5 SG rating is the hard limit: fill it with a denser liquid than it is rated for and you overload both the tank wall and your frame. Match the SG, confirm the resin, and spec fittings and gaskets to the liquid - not to what is on the shelf. See the technical drawing on this page for outlet and lid placement.
This applicator tank ships LTL freight from the nearest Norwesco plant to you - Lancaster, OH; St. Bonifacius, MN; or Tooele, UT - with the mode quoted live to your ZIP. Get a real number on the Freight Cost Estimator or call 866-418-1777. For DOT and agricultural-use context on applicator and loaf-style tanks, see our guides on Norwesco applicator and leg tanks for fertilizer and the 49 CFR 173.5 agricultural exemption.
