I need to replace some of the tires on a dually. Right know it's running two different tire sizes. The front pair are 215/85r16 while the rear are 235/85r16. I couldn't find the tag that indicated what the oe tires were. I'm just looking for replacements since it will be used as a dd, towing, and probably a few or things. Does anyone know what the oe tire sizes are for a 94 k3500? Should all the tires be the same size or should I leave it as it is and replace the bad ones?