Tire size alternative

ahill261

Senior Member
Joined
Feb 4, 2006
Posts
258
Location
Cinnaminson
I'm running stock Goodyear Endurance ST235/85R16 on my 2015 Pinnacle with gross weight of #16k. I'm not sure if they are maxed out. Any alternative suggests? Need to change rims with alternative?
 
You are probably not maxed out on those tires. 4079 pound capacity x 4 = 16316 LBS, deduct the pin weight that is sitting on the truck and you are probably only carrying about 13K on the tires
 
You are probably not maxed out on those tires. 4079 pound capacity x 4 = 16316 LBS, deduct the pin weight that is sitting on the truck and you are probably only carrying about 13K on the tires
The 235 is only 3640 according to Goodyear's site.

  • Load Range
    E
  • Load Index
    125
  • Speed Rating
    N
  • Measured Rim Width (in.)
    6.5
  • Section Width (mm)
    235
  • Revs Per Mile
    0
  • Max Load (lbs)
    3640
  • Max Inflation Pressure (PSI)
    80
 
Interesting, our Northpoint had those same tires but with a 129 load index.
The math still works, just a little closer depending on the weight balance of the trailer. 3640 X 4=14,560. using worst case of 15% of the total weight as the pin weight that would put 2400LBS on the truck and 13,600LBS on the tires. My experience has been that the pin weight is usually closer to 20% so that would take even more weight off of the tires.
AHill, you didn't mention but do you know what the axle rating is on your RV? I suspect they are going to be 7K axles so adding higher rated tires really wouldn't help as the weight rating of the tires already exceeds 7K per axle
 
We upgraded our Pinnacle to 245/70/19.5 using Boar wheels. Super tough tires. I does not look like the 19.5 Boar wheels are available anymore.

I would recommend upgrading to 17.5 wheels and a 235/75/17.5 tire. This is a standard commercial trailer tire. Available every where in load ratings 3,800 to 6,000. The commercial tires are much tougher than your standard Goodyear Endurance ST235/85R16 tire.
 

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When we had our Pinnacle I put a set of ST235/85R16 load range G tires on it. I can't remember the size of the GY's it came with but the new tires were slightly smaller in circumference which shouldn't be an issue for you. Sailun has a good reputation and has tires in that size. The rims on our Pinnacle could handle up to 120 psi so no problem with the higher inflation tires even though I ran them at 80 which was more than the load inflation chart indicated for my axle weights. Your rims should have a stamp somewhere showing their capacity. It does sound like staying with the Endurance is also a good option.
 
We have the 17.5 wheels and a set of Continental HTL2 Eco 235/75R/17.5" tires. They are an H rated tire and are a beast.
 
I'm running stock Goodyear Endurance ST235/85R16 on my 2015 Pinnacle with gross weight of #16k. I'm not sure if they are maxed out. Any alternative suggests? Need to change rims with alternative?
I'm running the same tires on my 2019 Jayco Seismic model 4212. Had several blowouts with Goodyear plus hard to find them at times. I was recommended to change to ST235/80/16 G rated. In the process of changing them out two at a time.
 
Yep, several blowouts with the GY endurance for me too. And a couple where the tread separated, so just missed a couple more blows!! I’m done with GYs!! I think the heavy Pinnacle needs a heavier tire anyway. The Endurance is only 10 ply.
So I went with 14 ply 235/85-16 Hartland from Discount Tire and love them.
From Texas: been to Montana, Maine, and several trips to Colorado and they are flawless. Hardly even worn!!

Mark
 
Yep, several blowouts with the GY endurance for me too. And a couple where the tread separated, so just missed a couple more blows!! I’m done with GYs!! I think the heavy Pinnacle needs a heavier tire anyway. The Endurance is only 10 ply.
So I went with 14 ply 235/85-16 Hartland from Discount Tire and love them.
From Texas: been to Montana, Maine, and several trips to Colorado and they are flawless. Hardly even worn!!

Mark
I'm running stock Goodyear Endurance ST235/85R16 on my 2015 Pinnacle with gross weight of #16k. I'm not sure if they are maxed out. Any alternative suggests? Need to change rims with alternative?
I ran those same tires for 7 yrs on my 36fbts 1 blow out road debris the 2nd was a faulty valve stem, have you ran your rig over the CAT scale? That’s the only way to be sure if you have maxed them out.
 
No matter what size/type of tire you replace yours with check with the manufacturer's inflation chart. You need to know the axle weight and adjust to that.
In my case I learned the hard way that too much pressure was not a good idea with cabinets vibrated open and everything on the floors. Bad for the cabinets too. After that I downloaded the Goodyear Endurance weight chart and adjusted from 65 down to 55 PSI for a safe weight carriage and a smooth ride.
 
Weight of 16K#
Is that your actual truck scale weight with the RV loaded to the heaviest you ever travel at or is it just some published number?

Don't forget you can not assume that a scale reading of 16,000 can be devided by 4 to learn the actual tire loading as it is well documented that the total weight is not evenly distributed between axles and certainly split 50/50 between the ends of an axle.

I have seen it suggested that you need to assume at least a 48/52% split between axles PLUS assume at least a 48/52% end to end split on the heavy axle.
 
I'm running stock Goodyear Endurance ST235/85R16 on my 2015 Pinnacle with gross weight of #16k. I'm not sure if they are maxed out. Any alternative suggests? Need to change rims with alternative?
I've been using Sailun ST235/85R16 on my 2016 Pinnacle FLSA for the past 4 years. The average tread depth is still at about 9/32" after quite a bit of travel/towing. I just went to the CAT scales and total trailer axle weight when hitched was 12760lbs. We re-measured with one axle on each scale. 6420 on front trailer axle and 6340 on rear, almost exactly 50/50 which we were happy about. I should have taken one more measurement with one trailer side off the scales to get a four point weight but did not take the time. There is some uneveness in the Sailun wear pattern, but nothing drastic. I am going to rotate for the first time and use for a couple more years before switching out to new Sailuns (which will likely not be due to tread wear). I know Sailun has had a great reputation on forums, but have not seen them mentioned in this thread. I keep the pressures at about 100psi. It may be hard to check your rims, but mine has a small indication on the inside of the rim that's hard to find that they are rated for 3750lbs.
 

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