I've got a Lariat Crew with 18 x 8.5" aftermarket wheels - a G-FX brand.
Currently has the stock tire size on them, 275/65/18.
I'd like to go wider and maybe an inch taller.
Got that info or have a chart for me?

Thanks.

 

Cooper ST Maxx:
http://us.coopertire.com/tires/discoverer-s-t-maxx.aspx
295 or 305/70r18 is likely what you're after.

 

I've got Coopers now actually. The size is what I was looking for - thanks for that.
The G-Fx wheel I have is discontinued so I was unable to get the specs for it.