Originally Posted by Steve Ownby
I may stand by my statement but I also stand corrected! I went back to look at the OP's tire size. At his size there is no difference in weight carrying at a given psi and the higher rating occurs at max psi. Turns out that the difference in weight carrying at a psi does not occur in smaller tire sizes. In the OP's wheel size of 19.5 you have to get up to 255/70 before you start to get a difference in weight at a given psi.
Very long story short; the OP is fine at a psi his G tire was inflated to, just be careful as yours could be different.
Here's an example using the Goodyear tire charts which show what I am saying.. Look at the bolded values for the same tire and size. There is a value for the F rated and a higher PSI for the G and H rated. If you change type and/or size of tire then this doesnt apply.