Can an ST175/80-13 Trailer be Used in Place of an ST185/80D13 Trailer Tire
Question:
ON my 1972 boat trailer I have 4 bolt hole rims 4 inches apart. Center hole diameter in rim is 2.54 inches. Current tires are ST185/80D13 size. Question: If I order 2 of your model AM3S120 tires on rims will they fit right on and work since they are ST 175 instead of ST 185. thanks
asked by: Dave
Expert Reply:
There are a couple of things to look at before ordering tires and wheels for your vintage boat trailer. You mentioned the pilot hole (center hole) is 2.54 inches diameter. This could be important depending on how the wheel mounts to the hub. If it mounts using lug nuts then a larger pilot hole diameter is fine. But if uses wheel bolts instead of lug nuts then the pilot hole has to be exact because that is how the wheel centers on the hub.
The pilot hole for tire and wheel combo # AM3S120 is 2.65 inches.
The ST175 tire is going to be 0.6 inches more narrow than an ST185 and about 0.4 inches shorter overall. There would not be any clearance issues but the capacity is going to be lower on an ST175. For # AM3S120 it is rated for 1,360 pounds at 50 psi.
The other option is to keep the wheels you have and just replace the tires using # AM1ST79 which is an ST185/80-13 tire. I have included a link to our tire help article for you to view.
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Products Referenced in This Question
Loadstar ST185/80D13 Bias Trailer Tire - Load Range D
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range D
- 185/80-13
- 13 Inch
- M - 81 mph
- Kenda
more information >
Product Page this Question was Asked From
Loadstar ST175/80D13 Bias Trailer Tire with 13" White Wheel - 4 on 4 - Load Range C
- Trailer Tires and Wheels
- Tire with Wheel
- Bias Ply Tire
- Load Range C
- 175/80-13
- 13 Inch
- M - 81 mph
- 4 on 4 Inch
- Steel Wheels - Powder Coat
- Kenda
more information >
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