Get ready for some great advice on this topic. My pennies worth are to
never run tires below reco. pressure unless you want more traction out
of a mud pit or to lower your vehicle to get it below a bridge. Low
pressure will cause more sidewall flex and lead to an overheat
failure. Get Trailer tires only as they will have an extra sidewall
layer needed for trailer sway that will wear on car tires. I learned
from Charlie Spratt that you want 10% min. of the total tow weight on
the ball to help prevent excessive rear end swaying. Finally, Walmart
sells mounted trailer tires, that's tires and rims together, ready to
go in 13", 14", 15" size that have a C rating. $79, not bad. You can
mount them at the pickpoint and be ready to haul.
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