Trailer Tire Size Chart – Get the perfect size for your trailer tires
Trailer tire sizes are broken into main groups 12 inches and smaller and 13 inches and larger. It’s absolutely necessary to use trailer tires for trailers, and not for cars as they are engineered for different usage. Check the below Trailer Tire Size Chart to find the perfect dimension of the needed tire, and it’s specifications like Load range, Rim width and overall diameter.
Looking for a general tire size chart and guide: check here
Trailer Tire Size chart
8 – 9 – 10 – 12 – Inch Trailer Tire Sizing
| Older Size | Tire Size | Rim Width | Load Range | Overall Diameter |
|---|---|---|---|---|
| – | 4.80/4.00-8 | 3-3/4 inch | B: 590 lbs at 60 psiC: 760 lbs at 90 psi | 16.1 inches |
| – | 5.70-8 | 3-3/4 inch | B: 715 lbs at 50 psiC: 910 lbs at 75 psiD: 1,075 lbs at 100 psi | 18.1 inches |
| 16.5 x 6.5 – 8 | 165/65-8 | 5-3/8 inch | C: 800 lbs at 70 psi | 16.5 inches |
| 18.5 x 8.5 – 8 | 215/60-8 | 7 inch | C: 935 lbs at 50 psiD: 1,165 lbs at 70 psi | 18.3 inches |
| – | 6.90/6.00-9 | 4-1/2 inch | C: 1298 lbs at 60 psi | 21.1 inches |
| – | 205/50-10 | 6 inch | B: 665 lbs at 30 psi | 18.3 inches |
| 20.5 x 8 – 10 | 205/65-10 | 6 inch | B: 910 lbs at 35 psiC: 1,100 lbs at 50 psiD: 1,330 lbs at 70 psiE: 1,650 lbs at 90 psi | 20.5 inches |
| – | 4.80-12 | 4 inch | B: 785 lbs at 60 psiC: 990 lbs at 90 psi | 20.5 inches |
| – | 5.30-12 | 4 inch | B: 840 lbs at 55 psiC: 1,045 lbs at 80 psiD: 1,250 lbs at 105 psi | 21.9 inches |
| – | 145/80-12 | 4 inch | D: 1,220 lbs at 65 psiE: 1,520 lbs at 80 psi | 21.3 inches |
13 – 14 – 15 – 16 – 17.5 Inch Trailer Tire Sizing
| Letter Size | Metric Size | Rim Width Range | Load Range | Overall Diameter |
|---|---|---|---|---|
| A78-13B78-13 | 175/80-13 | 4-1/2, 5, 5-1/2 | B: 1,100 lbs at 35 psiC: 1,360 lbs at 50 psiD: 1,610 lbs at 65 psi | 24.1 inches |
| C78-13D78-13 | 185/80-13 | 4-1/2, 5, 5-1/2 | C: 1,480 lbs at 50 psiD: 1,725 lbs at 65 psi | 24.4 inches |
| F78-14G78-14 | 205/75-14 | 5, 5-1/2, 6, 6-1/2 | B: 1,430 lbs at 35 psiC: 1,760 lbs at 50 psiD: 2,100 lbs at 65 psi | 26.3 inches |
| H78-14J78-14 | 215/75-14 | 5-1/2, 6, 6-1/2, 7 | C: 1,870 lbs at 50 psi | 26.7 inches |
| – | 8-14.5MH | 6 inch | E: 2,540 lbs at 85 psiG: 3,070 lbs at 116 psi | 27.7 inches |
| F78-15G78-15 | 205/75-15 | 5, 5-1/2, 6, 6-1/2 | B: 1,480 lbs at 35 psiC: 1,820 lbs at 50 psiD: 2,150 lbs at 65 psi | 27.1 inches |
| H78-15J78-15 | 225/75-15 | 5, 6, 6-1/2, 7 | C: 2,150 lbs at 50 psiD: 2,540 lbs at 65 psiE: 2,961 lbs at 90 psi | 28.4 inches |
| – | 7.00-15LT | 5, 5-1/2, 6 | E: 2,403 lbs at 70 psi | 29.4 inches |
| – | 235/80-16 | 6, 6-1/2, 7, 7-1/2 | D: 3,000 lbs at 65 psiE: 3,500 lbs at 90 psi | 30.9 inches |
| – | 235/85-16 | 6, 6-1/2, 7, 7-1/2 | E: 3,640 lbs at 95 psiF: 3,960 lbs at 110 psi | 31.6 inches |
| – | 7.50-16LT | 6 | D: 2,590 lbs at 60 psiE: 2,926 lbs at 75 psiF: 3,168 lbs at 85 psi | 31.8 inches |
| – | 215/75-17.5 | 6-3/4 inch | H (single): 4,805 lbs at 123 psiH (dual): 4,540 lbs at 123 psi | 30.2 inches |
Trailer Tire Size Conversion Chart
| Old Tire Size | Current Tire Size |
| B78-13ST | ST175/80R13 |
| C78-13ST | ST185/80R13 |
| F78-14ST | ST205/75R14 |
| G78-14ST | ST215/75R14 |
| F78-15ST | ST205/75R15 |
| H78-15ST | ST225/75R15 |
Trailer tire width size
The trailer tire width refers to the distance from the widest point of a tire’s outer sidewall to the widest point of its inner sidewall; this distance is measured once the tire is mounted on the wheel it is going to be used with.
- Metric: A three-digit number follows the letters that identify the service type. This number designates the width of the tire in millimeters. For example, if a tire’s size was ST175/80-R13 LRD, the 175 identifies the section width as 175 millimeters.
- Numeric: The first set of numbers identifies the section width in inches. For example, if the tire size is 4.80 X 12B, then you know the section width is 4.80 inches.
Trailer Load Range Chart
Each Special Trailer (ST) service tire has a rated load range. The appropriate load range is represented by a letter within each tire size – B, C, D, and E. Each letter correlates to the ply rating (a number of tire plies) and load pressure (in psi units) for each ST and LT tire. That tells the maximum weight load tire can handle at its full rated PSI pressure.
- B – 4 Ply Rating, 35 psi (240 kPa)
- C – 6 Ply Rating, 50 psi (350 kPa)
- D – 8 Ply Rating, 65 psi (450 kPa)
- E – 10 Ply Rating, 80 psi (550 kPa)
| Load Range | Ply | Pressure |
| B | 4 | 35 psi (240 kPa) |
| C | 6 | 50 psi (350 kPa) |
| D | 8 | 65 psi (450 kPa) |
| E | 10 | 80 psi (550 kPa) |
What is the most common trailer tire size?
A common trailer tire size is ST225/75R15, commonly used for travel trailers, boat trailers, pop-up campers and all high-load carrying trailers including utility. ST stands for special trailer and indicates that this tire is designed to be used on a trailer. 225 is the width of the tread in millimeters. 75 is the height of the sidewall represented as a percentage of the tread width. 15 is the size of the rim this tire mounts on. In the case of a 225/75R15, the tire is roughly 9 inches wide, 28 inches tall and mounts on a 15 inch rim.
Can I use car tires on a trailer?
Don’t use car tires on trailers. Trailer tires and car tires have different structures to work with different loads. Especially using a trailer tire on your car, or a car tire on your trailer, could lead to serious accidents. Looking for car tire sizes, check here
Is a wider tire better on a trailer?
Wider tires = more road resistance = more power required to pull = lower MPG while towing. Trailer builders use smaller tires to save weight and cost. The larger your tire, the more of a grip your trailer has on the road. As a tire’s width increases, it covers more surface area on the road.
Picture by Benjamin Zanatta on Unsplash
Trailer Tire sizes explained
Related Tire Size Charts
- Tire Size Chart for all vehicles: What do tire size numbers mean?
- Toyota Tire Size Guide (Size Charts and Dimensions Included)
- Honda Tire Size Guide And Types of Tires
- Chevrolet Tire Size Guide for Different Models
- Ram tire size guide for all models (size charts and dimensions included)
- Tesla Tire Size by model and year
- Truck Tire Size Chart And Sizing Guide
- Car Tire Size Chart And Sizing Guide
- Cateye Tire Size Chart: Measurements
- Jeep Tire Size: find the perfect tires for your jeep
- Understanding a Tire Speed Rating Chart – why is Speed rating important?
- Trailer Tire Size Chart – Get the perfect size for your trailer tires
- Continental Tire Size Chart
- Michelin Tire Size Chart
- Tires Charts
The tire chart needs to tell me how wide the tire is.
I’m comparing a 5.70×8 tire to a 16.6x 6.5×8. The overall diameter
is good to know but what is the width of each? The 16.5 must be wider
because it lists the rim as being wider.
Good point, let us check it out for you and come back to it. thanks for reaching out. P