Upsizing Tire Size.

traveldawg

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Anyone go from a ST235-80R16G to a ST235-8516G??

I have Sailuns now and am considering replacing with the next size up. It gets me a shade higher which I can use. They can carry a heavier weight to so maybe I get a bit more safety margin.
 
Anyone go from a ST235-80R16G to a ST235-8516G??

I have Sailuns now and am considering replacing with the next size up. It gets me a shade higher which I can use. They can carry a heavier weight to so maybe I get a bit more safety margin.

If you still have the trailer listed in your signature, the 310GK, it looks like the GVWR of that trailer is 15,000 lbs.....correct? So if you have the trailer loaded to it's GVWR of 15K, there should be approx at least 3000 lbs of that weight on the pin and that leaves approx. 12,000 lbs on the 4 trailer tires. The "G" rated tires, if I'm not mistaken are 4080 lbs when inflated to the max. sidewall pressure, so you have a total of 16,320 lbs of load capacity available for what is probably only ~12,000 lbs on the tires themselves. That leaves you with a reserve total of 4320 lbs.....or approx. 1080 lbs per tire.

Are you looking to replace them just to gain more load capacity reserve.....or do you actually need to replace the tires because of age and/or wear. I'm just curious here.
 
Larry I was going to go to 85's on mine as well and decided it was overkill and just tightens up already tight clearances in the wheel well. As xrated stated the 235-80's have more than enough weight reserve for my trailer and didn't want to make it ride any harder than necessary. I'm at ~ 12700 pounds on the axles now so I have over 3000 pounds reserve capacity with the smaller size. Your 310 should be considerably lighter than mine so it might be overkill.
 
I went up to a 16" rim and Cooper LT tires. Tired of the ST tire hassle and worrying about tire failures.
 
I went up to a 16" rim and Cooper LT tires. Tired of the ST tire hassle and worrying about tire failures.

Personally, I would never use an LT tire for trailer service. There is a reason that ST tires have stiffer sidewalls and are more durable for trailer service. To each their own.
 
Anyone go from a ST235-80R16G to a ST235-8516G??

I have Sailuns now and am considering replacing with the next size up. It gets me a shade higher which I can use. They can carry a heavier weight to so maybe I get a bit more safety margin.

I went to the 85 series a couple of years ago. Great tires and no problems with the extra1/2".
 
I went to the 85 series a couple of years ago. Great tires and no problems with the extra1/2".

Thanks, Just Krusey. I was pretty sure they would fit. There seems to be plenty of room in the wheel well area. I appreciate the feedback.

rxated: mostly I want the extra hight - I can use a bit more clearance between the truck bed and RV. And since the carry a bit more weight then it doesn't hurt anything.

I have about 12,800 lbs on the axels. I knew the 80's were ample, again, just looking for some height.

Some 17.5" Goodyear KMAX J rated tires would be pretty cool.
 
As long as that extra inch of diameter doesn't put your tires inside the min clearances necessary between tires and tires to frame... go for it.
 
I just found out that new Solitudes (and Momentums) can come with 17.5" tires. So I'm pretty sure I am good-to-go....

Probably not going to make the change until the fall as I'd have to spring for new wheels too.
 
Just a thought, look at your spring condition with some measurements and comparison side-to-side. You may find you can spend that tire money alternatively with fresh, higher capacity, additional leaf springs that give you better height along with the obvious benefits if your springs are getting tired. You already have addressed the other weak points so why not a grand slam!
 
I just found out that new Solitudes (and Momentums) can come with 17.5" tires. So I'm pretty sure I am good-to-go....

Probably not going to make the change until the fall as I'd have to spring for new wheels too.

A 17.5 rim doesn't mean the tire has a larger diameter. I think I read somewhere that the 17.5s on the momentums are actually a little smaller overall.
 
A 17.5 rim doesn't mean the tire has a larger diameter. I think I read somewhere that the 17.5s on the momentums are actually a little smaller overall.

yep - last night I was doodling around on the 'net' and figured out that the Cooper Roadmaster ST215/75R17.5 has a 30.5" diameter and the Sailun ST235/85R16 diameter is 31.7. Looks like I am thinking about just going with the Sailun when I replace my current tires. At least I won't have to buy new rims. hooray.... :)
 

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