I have a 1/2 ton suburban that has 22 inch rims with semi low profile tires on it. I can't remember the actual sidewall height but they are performance tires and not really for towing. I tow my 25 foot Nordic with it but its only a 6 mile round trip to Windsor and back. I just bought a 26 foot travel trailer that weighs roughly the same as the boat does including the trailer and fuel, about 5,000 lbs. or so. Does anyone do any serious towing with a similar setup??? By the way, the sub has the full tow package including air shocks and the trailer has the load distributers/equalizers. Thanks for any info!!
I had 315/40/24s on my 04 Hemi truck and towed my wakeboard boat, and a friends 28ft Magic all the time with no problem (over 55 at that!!). I bottomed alot because the truck was so slammed, but the tires held up well. Good luck.