I think it's either 235/55-17 or 235/50-18, but anyway . . . your OE inflation of 32 psi is good for a rated load of approximately 1590 lbs (base 17's) or 1530 lbs (optional 18's). Call 1560 a good average for this.
The 265/35-20 has a smaller air volume and will need slightly more inflation pressure in order to maintain the same load capacity. In order to match the OE rated load of ~1560 lbs, you should probably be running 36 psi in those tires. At least 35 psi, just to match the lower 1530 number.
Most tires are good for at least 44 psi maximum inflation pressure, so you still have some margin left (but please check your specific tire choice to be sure). I'll also note that tires in this size are likely to carry an 'XL' load rating (extra load capacity) and suggest that you choose from those tires that do.
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If you have 20" wheels... - 
