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yellowdog00's avatar
yellowdog00
Explorer
Jul 24, 2016

Tire and Rim size question - Need some help please

I had a flat (sidewall blowout) on one of my fiver tires last Thursday when I was about 40 miles from our CG at St. Mary, MT. Put the spare on and stopped in nearest town where tire shop only had a 235/85 R16 tire, load range F. Samson brand. Only tire close to what I have on camper. Existing tires are Rainiers 235/80 R16 load range E. I'm now nervous about a couple things since I have to make a 1700 mile trip back to Midwest.

Questions
1. Am I doing any damage to anything by having the one slightly larger Samson tire on the fiver along with the other three. There is plenty of clearance, just don't know what difference the slightly larger diameter makes. I let the dealer put it on in lieu of the spare for the extra load capacity. This was rear tire under the kitchen side. I'm considering going back to dealer and having the three other tires replaced by same size Samsons.

2. My rims have a max load of 3580 stamped on them.. Cannot find a max pressure. Am I going to have problems with the higher pressure tires? 95psi vs 80on the Rainiers.

Would appreciate any helpful guidance before I head back home next week.
  • First, thanks to everyone who took the time to reply.

    I called Jayco this morning and they were unable to verify if the Al rims on my camper would handle load range F tires and the 95 psi. Only that it came with 80 psi tires. Since the only tire size I could get now was the 235/85 R16, I elected to get another one and put it opposite the one I got last Thursday and kept the tire I replaced. I will have a spare and an extra tire for trip home. These are definitely much heavier tires than the Rainiers I replaced. I will replace the other two when I get home.

    This would be a lot easier if I were home but who can complain much while camping at east entrance to Glacier NP.

    I do want acknowledge the owner and staff at Nevins Tire Centre in Browning, MT. Both days they got me in and out as quick as they could and treated me fairly on price..

    Made a stressful situation easier to handle being so far from home.
  • How long are you staying at the CG? Could they order you the tires you really want, rather than making do with what they have on hand?
  • No problem with a slightly larger size tire on one corner. All the trailer tires spin independently. Only potential issue is if they're torsion spring axles then the larger tire will take slightly more load.
  • Generally our newer trailer wheels with 3500-3700 lb capacity are good for 110 psi. Your 2016 trailer wheel may have that pressure rating. We can't tell you what you have.
    A 1-800 to Jayco should give you a answer. Most of the foreign made trailer wheels may not have a max pressure stamp/sticker which may be on either side of the wheel or in the valley. Check to be sure.

    Your not doing any damage to the trailer by running a different diameter tire. Nothing in common with say using different diameter tires on your truck tires.
    Just be aware because of the different tread pattern and different tire diameter at each end of a axle its brakes can have different braking performances....especially on wet pavement. One tire may slide while the other just rolls during a hard braking event. No big safety deal.

    The bigger problem is running those low cost ST tires on a 15250 GVWR trailer.
    I would spend the money and upgrade to a Sailun S637 load range G at 4080 lbs and 110 psi. This is a commercial grade all steel ply carcass tire.
    It comes in a ST235/80-16 size...or a ST235/85-16 size all in a good price for what you get.

    The Goodyear G614 in a LT235/85-16 G at 3750 lbs @ 110 psi is another commercial grade all steel ply tire made for the regional service trailer industry. Good tire but pricey.

    If you stick with a ST load E tire the Provider by Taskmaster is popular with haulers and has a M speed rating. Many ST tires are speed restricted to 65 mph.
  • On a trailer, I don't think you or the trailer will notice one tire being slightly larger. If the tires are getting older, perhaps for peace of mind I would change the other tires as well, but that is up to you. I don't let mine go past 5 years from the date on the tire. It is unlikely the extra 15 psi will be an issue for the rim. It is pretty rare to hear of a rim failure. I couldn't find a load or pressure rating on my rims and I went from LRC to LRD (50 psi to 65 psi) and I've had no issues. Good luck with whatever you decide.
  • Watch those Rainers very close; they are famous for developing a big blister on the sidewalls, check very good inside and out. Bro in law bought a new Penicale and didn't make 1000 miles before 2 of them developed a 'goose egg' on the sidewall; You need Goodyear G614 or Sailuns S647
  • If the other tire on the side where the failure occurred picked up the extra weight it will most likely fail very soon. Time for four new tires.

    Chris
  • Tires should be matched by axle, at a minimum. So at a minimum you should get one more on the other side of that axle, then you can use the old one for space. I, personally, would not run different tires on the two axles though, so getting three more would be the best.
  • I am no tire expert but I would not worry going to heavier tier maybe get another for other side of that axle, and you can run it at less than the 95lbs as it has more carrying capasety.
    Frank.