Forum Discussion

kohana's avatar
kohana
Explorer
Feb 18, 2017

At what pressure do you run your Sailun tires?

I'm replacing my E rated Michelin Ribs with Sailun 235/85/16G tires. The scaled weight on my trailer wheels is just under 11200lb, about 2800lb/tire avg. My rims are G rated. I run the E tires @ 80lb...
CALandLIN's avatar
CALandLIN
Explorer
Feb 19, 2017
fj12ryder wrote:
"Tire industry standards suggest - with strong wordings - that OE tires be inflated to the vehicle manufacturer recommendations - almost always what the side wall says."

IMO this is very much a CYA by the industry, both trailer, and tire. No one wants a lawsuit based on the statement that "They said my tires didn't have to be inflated that much", after the tire self-destructs because it was under inflated for the load it was carrying. Easiest, and probably recommended by the lawyers, to say "Fill 'em full".

Sez who? Why does it matter as long as my tires equal or exceed my GVWR. If I have 13,000 lbs. on three axles why do I need tires that can carry 24,000 lbs.? Please cite the regulation. And 6 "E" rated LT tires at 3,000 lbs. will equal my GVWR of 18,000 lbs. And more than equal when you figure 3,600 lbs. off for pin weight.


But, who is covering what? FMVSS instructs the vehicle manufacturer to use tires with a load capacity equal to or greater than the vehicle's GAWRs. Then they tell them to use an appropriate amount of inflation pressure in each tire to insure they can carry the load of the GAWRs.

"Replacement tires must have a load capacity equal to or greater than the OE tires provided. Plus sized tires should have an inflation pressure set at a value that provides enough load capacity to equal or exceed what the OE tires provided."

In every tire manufacturers SOP there is a statement that requires replacement tires to have a load capacity equal to the OE tires or greater than that load capacity. They are not going to trump the vehicle manufacturer's OE tire selection. Why? Because NHTSA has given the vehicle manufacturer sole responsibility for OE tire selection.

NHTSA requires automotive tire fitments to have some load capacity reserves. Trailer's do not get that luxury. Besides that, tires are not selected for any vehicle's GVWR. They are selected to support the axle they are fitted to.

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