Trailer Tire Speed and Weight Ratings
Question:
I built a small tear camping trailer on a Harbor Freight Haul Master utility trailer. The wheels have a sticker on them saying warning maximum highway speed 55mph. The tire speed rating is 72m, which according to their owners manual is 81mph. The tires are 12”, wheels have a 4 lug pattern. I don’t know how fast I should go. Do you have an answer?
asked by: Mike M
Helpful Expert Reply:
Trailer tire speed ratings do use a letter code system. A tire rated L for speed means it can be operated up to 75 mph; a tire rated M for speed can be operated up to 81 mph. There are many other speed codes. A trailer tire that does NOT indicate any specific speed rating on its sidewall should be presumed to be rated for 65 mph. If your tires do not indicate a speed rating that is molded right into the tire's sidewall then you should go by what the trailer documentation says.
It is possible your tires have the default 65 mph speed rating but the trailer maker chose to recommend a lower speed (by applying the sticker) for liability reasons. Keep in mind that the manufacturer probably did not intend their item to be converted into a camper.
Trailer wheels like 12-inch 4-lug wheel # AM22318HWT are not speed rated, but they are load rated for weight. This wheel is rated for up to 1220-lbs, but if it were to be paired with a tire that has a lower weight rating then that lower tire rating becomes the overall limit. If it were to be paired with a tire with a higher rating like # AM10140 (rated for 1520-lbs) then the lower WHEEL rating applies.
When a wheel and tire differ in weight capacities the lower of the two ratings applies to the combined wheel and tire.
I linked our main page for 12-inch 4-lug trailer wheels and tires to choose from. . I also linked some helpful articles and a video on trailer tires.
Products Referenced in This Question
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 >
Product Page this Question was Asked From
Aluminum Split Spoke Trailer Wheel - 12" x 4" Rim - 4 on 4
- Trailer Tires and Wheels
- Wheel Only
- 12 Inch
- 4 on 4 Inch
- Aluminum Wheels
- Boat Trailer Wheels
- HWT
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Shop: Kenda Karrier ST205/75R15 Radial Trailer Tire with 15" Black Mod Wheel - 5 on 4-1/2 - LR D
- Shop: Kenda 205/65-10 Bias Trailer Tire with 10" Galvanized Wheel - 5 on 4-1/2 - Load Range E
- Shop: Kenda Karrier ST175/80R13 Radial Trailer Tire with 13" Black Mesh Wheel - 5 on 4-1/2 - LR C
- Shop: Westlake ST205/75R15 Radial Tire w 15" Condor Aluminum Wheel - 5 on 4-1/2 - LR D - Gunmetal
- Shop: Kenda 205/65-10 Bias Trailer Tire with 10" White Wheel - 5 on 4-1/2 - Load Range E
- Q&A: Does Kenda Karrier ST175/80R13 Radial Trailer Tire & Black Wheel Come Balanced
- Q&A: Do Trailer Tires Have Speed Ratings
- Video: Checking Out the Kenda 5.70-8 Bias Trailer Tire with 8" White Wheel
- Shop: Kenda 205/65-10 Bias Trailer Tire with 10" Galvanized Wheel - 5 on 4-1/2 - Load Range C
- Shop: Karrier ST205/75R15 Radial Trailer Tire with 15" Aluminum Wheel - 5 on 4-1/2 - Load Range C
- Search Results: 530 12 trailer tire
- Q&A: How to Select Trailer Tires with Correct Load Range Rating for Trailer Gross Weight
- Shop: Trailer Wiring
- Search Results: lug nut
- Search Results: trailer wheel lug nut
- Search Results: 12cln~l
- Search Results: spare tire mount
- Video: Breaking Down the Westlake ST205/75R15 Radial Tire w 15" Condor Aluminum Wheel
- Article: How to Wire an Electric Winch
- Video: CE Smith Spare Tire Carrier for Trailers Review
- Article: Trailer Tire Sizing
- Q&A: Can a 5.30-12 Size Tire be Replaced with a ST145/R12 Size Tire
- Q&A: Recommended Trailer Tires To Replace Older ST185/70R13 Tires
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Video: All About the Counteract Tire Balancing Beads for 1/2-Ton, 3/4-Ton, and 1-Ton Trucks
- Shop: Trailer Hitch
- Shop: Suspension Enhancement
- Q&A: What Is The Recommended Lug Nut Torque On 7,000lb Axles?
- Q&A: Balance Beads to Use with Kenda Karrier ST175/80R13 # AM31990
- Search Results: lions head