I have the BFG 285/65/18 tires that are 32.7" tall and I could not imagine going to a taller size without something hitting/rubbing at full turn and compression.
The next size up is the 305 and it is 33.7" tall, they would put the distance between the mud flap and tire at less than 1/2" just sitting there.

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2007 Tundra DC Limited 5.7L 4X4
TRD,NAV,TOW
Xlerator Exhaust
aFe Stage 2 CAI
BFG AT/KO 285/65/18
Desert Sand Mica