As I recall those wheels are 7" wide so you can't go totally hog wild with tire sizes. The max would probably be a tire with a section width of about 10" at the very most......like a 245/50. That's pushin' it.
I would go to www.tirerack.com and look up some of the sizes you're interested in and then click on "specs". It'll show the minimum and maximum rim widths recommended.
My own experience has been the the "minimum" recommended rim width is usually too narrow and you end up sorta squeezing the tire on the rim, which isn't the end of the world, but the tire doesn't work right that way, especially if you're into hard cornering activities.
Not to beat anything into the ground, but what aspect ratio tires are you guys talking about? 50 series? 60 series?
I'll bet any tire store that was truthful would tell you that a 265/60 or 265/50 should really be mounted on at least an 8" rim, otherwise the sidewalls get pulled in.
But maybe I'm misunderstanding the orginal question....
Are we talking about the biggest size that'll fit in the rear fenderwells or the biggest size to fit properly on the rim ?
Oh well, not that big a deal anyway .......whatver works, works !
i have put 255/60/15's on turbines and have seen 275/60/15's on turbines. why the wide tire?
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rear tire size 
