Is Trailer Tire Size ST145R12 Slightly Larger than Tire Size 4.80-12
Updated 10/22/2025 | Published 04/12/2025
Question:
I’m wanting to make sure the st145 r x12 5 bolt rim tire combo will replace my 4.80 x12 bias ply tire combo on a boat trailer it seems just a little larger. Thank you for your time.
asked by: Gene
0
Expert Reply:
Hey Gene, yes an ST145R12 tire size like the # AM10140 is a little bigger than a 4.80-12 tire size by about .8 of an inch in height and .8 inches wider.
That extra width and height most likely wouldn't be enough to cause any clearance issues unless your current clearances are just barely enough.
expert reply by:
Jameson C
0
Product Page this Question was Asked From
Kenda Karrier S-Trail ST145/R12 Radial Trailer Tire - Load Range E
- Trailer Tires and Wheels
- Tire Only
- Radial Tire
- Load Range E
- 145/80-12
- 12 Inch
- M - 81 mph
- Kenda
more information >
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Jameson C.
10/22/2025
Hey Gene, how did the ST145R12 tire and rim combo end up fitting on your boat trailer? Your update could make it easier for the next person looking to move up from a 4.80-12 setup.