I see you have a Triton, I wonder if that may be a factor as well as the Ranger appears to be about 350Kg or more lumpier on the road unloaded? Not sure that the profile would have much bearing on it 265 vs 275 but it could well be a factor combined with 350Kg+ less lard sitting on them. I have to run mine at 36psi in the Ranger to avoid uneven wear across the tread surface, no way I would get away with 34 but anything more is quite sharp to the point of harsh with the aftermarket shocks/struts and rear leafs in mine.
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