Recommended Replacement Tire for my F78-14st Tire.
Question:
My current tires on my trailer are F78-14st. Im not seeing the normal tire code that Im used to say a, ST205/75D14. Im not sure what tire size I should be looking for. Also, If I measure the diameter of the rim, its 15 inches. But some pages online are saying that the F78-14st is a ST205/75D14 size. It doesnt seem to add up. Any help would be appreciated.
asked by: Bruce
Helpful Expert Reply:
Your trailer tire size F78-14st is an older tire size. The new label for that tire size is ST205/75D14. They are the same tire basically, but different size label. Your tire size is likely 14 inches instead of 15 inches because to measure the diameter of your tire, you do not measure the lip of the wheel. You only measure the part of the wheel the tire has contact with, also called the bead seat.
With your tire size in mind I have two tire recommendations for you. If you do more highway driving with your trailer I recommend using a radial trailer tire like the Taskmaster Radial Trailer Tire - Load Range C # TR20514. This tire will replace your current tire on your trailer. This tire has a 1,760 lb. max load at 50 psi. This tire has a maximum speed of 81 mph.
If you want to just replace your tire with the same type of trailer tire, the Kenda ST205/75D14 Bias Trailer Tire - Load Range C # AM1ST52 is what you will need. Bias ply tires are good for utility and off-road use as they have thicker side walls. This tire has a 1,760 lb. maximum load capacity at 50 psi. This tire has a maximum speed of 81 mph.
I recommend the radial tire over the bias ply tire because a radial tire flexes more than a bias tire, giving it better ground contact, traction, stability, and tread wear.
I attached two review videos for both the Radial and Bias Ply tires you may find helpful.

Products Referenced in This Question
Kenda ST205/75D14 Bias Trailer Tire - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range C
- 205/75-14
- 14 Inch
- M - 81 mph
- Americana
more information >
Product Page this Question was Asked From
Provider ST205/75R14 Radial Trailer Tire - Load Range C
- Trailer Tires and Wheels
- Tire Only
- Radial Tire
- Load Range C
- 205/75-14
- 14 Inch
- M - 81 mph
- Taskmaster
more information >
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