What Should 18 Ply Trailer Tire be Inflated to
Updated 09/26/2025 | Published 04/30/2025 >
Question:
I purchased four 18-ply wheels as an upgrade for my trailer, replacing the previous 14-ply wheels due to frequent tire failures. What tire pressure is recommended for summer operation in temperatures exceeding 100 degrees Fahrenheit
asked by: Miguel
Expert Reply:
Hey Miguel, while I don't know exactly what tire and wheel combo you have I can use the Triangle 235/75R17.5 Radial Tire w/ 17-1/2" Modular Wheel # TR75ZR that you referenced as an example as it is an 18 ply tire. This tire needs to be inflated to 125 psi when cold to ensure you get the full weight capacity and prevent heat build up.
If you have a different tire though you would need to check the sidewall for the max PSI Rating and inflate to that as that's how trailer tires are designed.
Product Page this Question was Asked From
Triangle 235/75R17.5 Radial Tire w/ 17-1/2" Modular Wheel - Offset - 8 on 6-1/2 - LR J - Black
- Trailer Tires and Wheels
- Tire with Wheel
- Radial Tire
- Load Range J
- 235/75-17.5
- 17-1/2 Inch
- J - 62 mph
- 8 on 6-1/2 Inch
- Steel Wheels - Powder Coat
- Triangle
more information >
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Jameson C.
9/26/2025
Hey Miguel, did inflating your tires to 125 psi help with the heat buildup during your summer travels? I'm curious to know if this solution worked for you, as it could help others facing similar tire issues.