Depending on the weight of your truck, people in it, gear, etc. I have found that 40 to 50 works good. I have smaller tires but an "E" rating and I run 43 front and 40 rear. 3psi isn't a big deal, but I've tried the water thing, chalk thing, and felt the ride at many pressures and I like this best.
<font face="Comic Sans MS"> Do the chalk line test. If you're not sure what this is, just do a search of this forum for chalk and set the date range to all. [img]/wwwthreads_images/icons/crazy.gif[/img] That's the best method because it can vary depending on equipment and other options in the truck (heavy stuff in there, etc...)...</font>
dad's running 50 psi in his 285s on his 2500 diesel. the tread is NOT even...there's about .75" on the ouside of the tire that does not touch the ground. he's runnning higher psi cause he's towing the 36' combine header.
<font color=blue>Shorts</font color=blue><-- its not what you think...and don't ask what it is [img]/wwwthreads_images/icons/smile.gif[/img]