7.50-16 Bias Ply
PSI
30
C,D,
E
35
C,D,
E
40
C,D,
E
45
C,D,
E
50
D,E
55
D,E
60
D,E
65
E
70
E
75
E
Lbs per
tire-
Single
1620 1770 1930 2060 2190 2310 2440 2560 2670 2780
Lbs per
tire-
Duals
1430 1565 1690 1815 1930 2040 2140 2245 2345 2440
Looks like 50 PSI would be a good choice for both the front and rear tires in the chart
above. The placard for this particular motorhome said 60 PSI. This is probably because of
the accepted rule to add 5 – 10 PSI if you intend to hit 65mph or better and also to help
cover a bit of loss between air checks. A Load Range D or E tire will do the trick if you
never cold inflate over 60 lbs. If you think you need 65 lbs., A Load Range E tire would be
required. Incidentally, many of these tires have a maximum speed rating on them. 65Mph
max is not uncommon. Also, Bias Ply tires are probably not what you will use today.
Looks like 50 PSI would be a good choice for the radial tire in the chart below from
Michelin. Bumping by 5 – 10 PSI will get you to 60 PSI for the same reasons noted above.
Note that this chart says “per position”. That means the left rear, right rear, left front or
right front. That also means that the capacity listed for the rear duals is for a PAIR of tires.
These Radial tires are maximum rated for 3,042 lbs. each – when inflated to 80 PSI. That
doesn't mean you can put 80 PSI in each tire and increase the capacity for the axle. Nor
should you just inflate to the max without a reason. Overinflation is almost as bad as
underinflation for handling. All you are really doing by adding too much air is making the
ride harder, and messing up the handling. Do it right. There is an optimum pressure for your
tires, giving the highest possible grip. Any pressure over this will bulge the tread in the center
causing a loss of traction because there is less rubber in contact with the road, and any
pressure under this will cause excess distortion of the tire and a loss of traction.
LT235/85R16 LRE
PSI 35 40 45 50 55 60 65 70 75 80
Lbs per
position-
Single
1700 1870 2030 2205 2335 2485 2623 2765 2905 3042
Lbs per
position-
Duals
3090 3400 3690 4015 4250 4520 4765 5030 5290 5556
One more thing. Use the size tire recommended by the manufacturer. This is especially
important to ensure the tires match the rim's capacity, fit in the wheel well, and in the case of
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