Trailer Tire Sizing

8 - 9 - 10 - 12 - Inch Trailer Tire Sizing

4.80/4.00-8

~4.6"

3-3/4"

B: 590 lbs at 60 psi
C: 760 lbs at 90 psi

16.1"

5.70-8

~5.8"

3-3/4"

B: 715 lbs at 50 psi
C: 910 lbs at 75 psi
D: 1,075 lbs at 100 psi

18.1"

16.5 x 6.5 - 8

165/65-8

~6.6"

5-3/8"

C: 800 lbs at 70 psi

16.5"

18.5 x 8.5 - 8

215/60-8

~8.9"

C: 935 lbs at 50 psi
D: 1,165 lbs at 70 psi

18.3"

6.90/6.00-9

~6.5"

4-1/2"

C: 1298 lbs at 60 psi

21.1"

205/50-10

~7.7"

B: 665 lbs at 30 psi

18.3"

20.5 x 8 - 10

205/65-10

~8.4"

B: 910 lbs at 35 psi
C: 1,100 lbs at 50 psi
D: 1,330 lbs at 70 psi
E: 1,650 lbs at 90 psi

20.5"

4.80-12

~4.9"

B: 785 lbs at 60 psi
C: 990 lbs at 90 psi

20.5"

5.30-12

~5.5"

B: 840 lbs at 55 psi
C: 1,045 lbs at 80 psi
D: 1,250 lbs at 105 psi

21.9"

145/80-12

~5.7"

D: 1,220 lbs at 65 psi
E: 1,520 lbs at 80 psi

21.3"

*The exact tire width varies from tire to tire. Check the section width on your tire's product page for specific measurements

13 - 14 - 15 - 16 - 17.5 Inch Trailer Tire Sizing

A78-13
B78-13

175/80-13

~6.6"

4-1/2", 5", 5-1/2"

B: 1,100 lbs at 35 psi
C: 1,360 lbs at 50 psi
D: 1,610 lbs at 65 psi

24.1"

C78-13
D78-13

185/80-13

~7.2"

4-1/2", 5", 5-1/2"

C: 1,480 lbs at 50 psi
D: 1,725 lbs at 65 psi

24.4"

F78-14
G78-14

205/75-14

~8.1"

5", 5-1/2", 6", 6-1/2"

B: 1,430 lbs at 35 psi
C: 1,760 lbs at 50 psi
D: 2,100 lbs at 65 psi

26.3"

H78-14
J78-14

215/75-14

~8.5"

5-1/2", 6", 6-1/2", 7"

C: 1,870 lbs at 50 psi

26.7"

8-14.5MH

E: 2,540 lbs at 85 psi
G: 3,070 lbs at 116 psi

27.7"

F78-15
G78-15

205/75-15

~8.1"

5", 5-1/2", 6", 6-1/2"

B: 1,480 lbs at 35 psi
C: 1,820 lbs at 50 psi
D: 2,150 lbs at 65 psi

27.1"

H78-15
J78-15

225/75-15

~8.9"

5", 6", 6-1/2", 7"

C: 2,150 lbs at 50 psi
D: 2,540 lbs at 65 psi
E: 2,961 lbs at 90 psi

28.4"

7.00-15LT

5", 5-1/2", 6"

E: 2,403 lbs at 70 psi

29.4"

235/80-16

~9.25"

6", 6-1/2", 7", 7-1/2"

D: 3,000 lbs at 65 psi
E: 3,500 lbs at 90 psi

30.9"

235/85-16

~9.37"

6", 6-1/2", 7", 7-1/2"

E: 3,640 lbs at 95 psi
F: 3,960 lbs at 110 psi

31.6"

7.50-16LT

D: 2,590 lbs at 60 psi
E: 2,926 lbs at 75 psi
F: 3,168 lbs at 85 psi

31.8"

215/75-17.5

~8.3"

6-3/4"

H (single): 4,805 lbs at 123 psi
H (dual): 4,540 lbs at 123 psi

30.2"

*The exact tire width varies from tire to tire. Check the section width on your tire's product page for specific measurements

Last Updated: 1/24/2024

Steven H.

5/18/2024

I have a 34 foot motorhome, Forest River Georgetown, and I was told the proper weight for the air is 92 pounds. I cannot find a placard anywhere and I looked in the owners manual which covers several different models but nothing specific about tire pressure in the manual. My question is this: If the tire pressure has to be 92 psi, what is the total pressure required from the compressor to pump the tires up to 92 psi? I have been told it's considerably more but until I can find out how much more, I won't know what kind of compressor to get or how to go about getting air in the tires when someone actually comes out to put it in by running a service call. Also, I can round down to 90 psi if it makes the mathematics and easier. Thank you very much for your kind reply.

Mark S.

9/9/2024

@StevenH A compressor capable of 92 psi will inflate the tire. It will be slow though as the tire and tank/compressor equalize to that pressure. Anything greater than 92 psi will allow faster filling of the tire.

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