When you’re hauling, the right tires are step one for safety and efficiency. Trailers aren’t a place for “any old tire.” Use trailer-specific (ST) tires designed for towing stability, heat resistance, and higher load at the correct pressure. You’ll see “ST” on the sidewall (vs. “P” for passenger or “LT” for light truck). Most ST tires are speed rated to 65 mph, though some are rated higher.
Safety tip: Always inflate ST trailer tires to the maximum cold PSI listed on the sidewall. Discount Tire offers free air checks to help you verify pressure.
Two specs work together to make sure your tires can carry the load:
You’ll find both on your tire’s sidewall. If you’re unsure, we’re happy to double-check your trailer setup and expected load.
Typical ST load ranges and pressures: - Standard Load (SL), 4-ply, up to 36 PSI - Extra Load (XL), 4-ply, up to 42 PSI - C1, 6-ply, up to 50 PSI - C2, 6-ply, up to 35 PSI - D1, 8-ply, up to 65 PSI - D2, 8-ply, up to 50 PSI - E1, 10-ply, up to 80 PSI - E2, 10-ply, up to 65 PSI - F1, 12-ply, up to 95 PSI - G, 14-ply, up to 110 PSI
General guidance: - Many utility and travel trailers use C, D, or E range tires. - Aim for a margin above your calculated need to reduce heat buildup and blowout risk. - Don’t over-spec too far—excessive stiffness can hurt ride quality and traction.
For heavier trailers and long-distance towing, ST radials with E, F, or G load ranges are common. Start with your trailer’s GVWR (trailer weight + max cargo) on or near the VIN placard, then divide by the number of tires to find the minimum per-tire capacity. Add a safety margin.
A proven heavy-duty pick: - Hartland ST Radial All Steel II: See the Hartland ST Radial All Steel II - Load Range G (14‑ply) with up to 110 PSI capability - All‑steel construction for stability, even wear, and heat dissipation - Rib design for a quiet, confident tow
Protect your investment with Certificates. If we can’t safely repair a covered tire, we’ll replace it with a brand-new one (or refund you). Learn how it works: Certificates Tire Protection
Horse and livestock trailers benefit from ST radial tires for smoother ride quality and highway stability. Choose the correct load range for your trailer’s weight and keep pressures at the sidewall max.
Great options: - Taskmaster Contender TTT868: Shop Taskmaster Contender TTT868 - Radial ST design with reinforced construction for long wear - M speed rating (up to 81 mph) - Goodyear Endurance: Shop Goodyear Endurance - Durawall technology resists cuts, tears, and punctures (ideal for gravel and rural routes) - Strong polyester casing with steel belts - N speed rating (up to 87 mph); load ranges typically D/E
It depends on your truck, load, and priorities.
When 19.5-inch makes sense: - Frequent heavy towing on 3/4-ton and 1-ton trucks - Need higher load capacity and stability than typical LT 17–20 inch tires - Comfortable running higher pressures (often 95–110 PSI) and a firmer ride
Benefits: - Higher load capacities (often Load Range G/H) and stiffer sidewalls reduce squirm - Better heat control under sustained heavy loads
Trade-offs: - Harsher ride and less off-road flex vs. LT tires - Requires 19.5-inch wheels rated for the pressure and load - Fewer all-terrain choices; typically highway/commercial tread designs
If you tow occasionally or prioritize ride comfort and traction versatility, high-quality LT tires in Load Range E (or F where available) are usually the better fit. For constant heavy fifth‑wheel or gooseneck towing, 19.5 can be a smart upgrade—confirm axle, wheel, and vehicle ratings first.
Dually trucks (e.g., F‑350, Ram 3500) benefit from tires that track true, run cool, and carry big loads with minimal sway. Focus on: - LT tires with appropriate dual load ratings (look for two numbers, e.g., 120/116) - Highway-terrain rib or highway all-season for maximum stability and longevity - All-terrain options if you split time between job sites and pavement
Popular, proven categories: - Highway/Commercial rib: Bridgestone Duravis (R500 HD/R238), Firestone Transforce HT2, Michelin Defender LTX M/S - Highway all-season: Continental TerrainContact H/T, Toyo Open Country H/T II - All-terrain (Load Range E): BFGoodrich All‑Terrain T/A KO2 (3PMSF), Falken WildPeak A/T3W (3PMSF), Toyo Open Country A/T III
Best practices for duals: - Match size, brand, model, and tread depth across each dual position - Maintain proper dual spacing and run recommended pressures for your load - Use the dual (lower) load rating when applicable
Typical U.S. conditions call for year‑round grip, rain performance, and stability under load. Choose by workload:
Notable examples by use: - Highway all‑season: Michelin Defender LTX M/S, Bridgestone Duravis R500 HD, Continental TerrainContact H/T, Firestone Transforce HT2 - Rugged/all‑terrain: BFGoodrich KO2 (3PMSF), Falken WildPeak A/T3W (3PMSF), Toyo Open Country A/T III (3PMSF), Cooper Discoverer AT3 LT (3PMSF)
Tip: F‑250/F‑350 often require LT Load Range E; verify your door‑placard specs and towing needs.
As always, confirm fitment and load requirements with your owner’s manual, door placard, or a tire expert. Our in‑store system will factor in your exact truck, wheel size, and towing/hauling profile.
Ready to dial in the perfect tire for your trailer or truck? - Get personalized picks fast: Start with Treadwell - Prefer face-to-face? Find a store and make an appointment - Shopping for your tow vehicle too? Shop truck tires