All trucks vary from one to the next so what fits on one might rub on another that being said.
275 65 20 typically fit, 285 60 20 will for sure fit, 285 65 20 should fit which would be the tallest 34.6" tall and 11.25" wide some say fit but are tight, some say they had a minor rub. 295 60 20 34" tall 11.5" wide might fit. 305 55 20 will fit 33.25" tall and 12.25" wide but you will have limited clearance between the sidewall and upper control arm with the factory wheels typically less than 1/4". The other thing to keep in mind is that the sizes listed by the manufacture are nominal and what match closest to the actual size and these dimensions will vary from manufacture to manufacture. A 285 60 20 from company A may be bigger or smaller than a 285 60 20 from company B so it's always best to go to manufactures website and see what the actual dimensions are. Both pics below came from this thread
https://5thgenrams.com/community/th...rubbing-would-love-some-advice-and-info.8157/
275 65 20 stock off road package
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A 285 60 20 ridge grappler would fit nicely and look really good. Stock without the off road package on the truck below
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