Is this the std Bias or the radial? Either way the 45 on the side wall is the MAX cold tire pressure. I have run a set of 33's std TSL and used to keep them fairly close max pressure,(5-10lbs from number) as I felt they road a bit better that way. I still had the flat spotting and the thump thump for the first few mins of driving but that's a swamper. Some will run less air in them for street use, but I always felt that at higher speeds they got a bit mushy at lower PSI. thus that is why I kept it on the high side.