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Old 11-17-2017, 05:28 PM   #21
CaptnJohn
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Originally Posted by MattE303 View Post
Thanks for the info, I emailed Alan and asked about running pressures lower than the max (110psi) for the Sailun ST tires. He said you absolutely can, and included a copy of the spreadsheet you mentioned (I attached an image of it, hopefully it's readable).


I'm glad you contacted Alan. Sailun 235/80/16 were great for my Montana at 4080 but 235/85/16 were found fresh for less. Bought them and run at 100 instead of 110 as I certainly do not need 4400# per tire. Sadly, Sailun doesn't make tires in smaller sizes for those with smaller and lighter RVs.


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Old 11-18-2017, 07:57 PM   #22
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Couple of things...Walmart mounts the tires no charge if you buy through WalMart.com.
Be careful about using the valve stems with nuts to justify running 110psi in aluminum wheels rated for 80psi. We all know that "E" commerce trailer parts place that seems to repeat that.
One more.....I'm almost all Carlisle HD now...5th wheel, utility trailer, and as of last week the double axle boat trailer. Only one left is the little "mud boat".
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Old 11-20-2017, 12:40 PM   #23
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Agreed. The really striking thing about this chart for me though, is that there seems to be a commonly held belief on RV forums that, unlike regular car/truck tires, ST (trailer) tires are designed to be used only at maximum rated inflation, and running anything less than that is likely to induce failure due to heat caused by excessive sidewall flex. At least that's what I always thought was being said. This chart implies that that isn't the case.
ST tires, just like many other products, have gone through an evolutionary process. In the beginning, Carlisle Tire was the mass producer. It was their recommendation and policy to use maximum inflation pressures. Even their warranty information required it. Problem was, plus sizing. Lots of people wanted "over kill" replacements but not at max inflation. 12% load capacity reserves seemed to be the target and it often required less than max inflation pressures. When asking Max Brennan - a Maxxis field rep - about inflation pressures, he supports the vehicle manufacturers/replacement tire retailer's recommendations. (Industry standards say to NEVER use less inflation pressure than what has been recommended on the tire placard or from deviations found in the individual vehicle owner's manual).

The caveat about using tire inflation charts/tables is to ask yourself; "Is this correct and safe".

Vehicles built under the guidance of FMVSS (standards) are built to minimum safety standards. That's what recommended tire inflation pressures are. When using less than an industry standard inflation pressure the whole field becomes unprotected from that action.
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Old 11-20-2017, 02:23 PM   #24
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I've been running my Sailuns at between 90-100 psi as I have less than 14K on three axles.
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Old 11-20-2017, 03:23 PM   #25
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Originally Posted by CWtheMan View Post
ST tires, just like many other products, have gone through an evolutionary process. In the beginning, Carlisle Tire was the mass producer. It was their recommendation and policy to use maximum inflation pressures. Even their warranty information required it. Problem was, plus sizing. Lots of people wanted "over kill" replacements but not at max inflation. 12% load capacity reserves seemed to be the target and it often required less than max inflation pressures. When asking Max Brennan - a Maxxis field rep - about inflation pressures, he supports the vehicle manufacturers/replacement tire retailer's recommendations. (Industry standards say to NEVER use less inflation pressure than what has been recommended on the tire placard or from deviations found in the individual vehicle owner's manual).

The caveat about using tire inflation charts/tables is to ask yourself; "Is this correct and safe".

Vehicles built under the guidance of FMVSS (standards) are built to minimum safety standards. That's what recommended tire inflation pressures are. When using less than an industry standard inflation pressure the whole field becomes unprotected from that action.
My trailer came with LRE tires, max 80 psi, and I think that's what the placard on the trailer indicates as well (need to double check), so my thinking is I should be fine running 80-90 psi in my Sailuns. Given the actual weight on the axles/tires of my fully loaded trailer (CAT scale weight), this amount is consistent with the chart from Sailun, and if I understand you correctly, consistent with what you are saying also...true?
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Old 11-20-2017, 05:19 PM   #26
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Originally Posted by MattE303 View Post
My trailer came with LRE tires, max 80 psi, and I think that's what the placard on the trailer indicates as well (need to double check), so my thinking is I should be fine running 80-90 psi in my Sailuns. Given the actual weight on the axles/tires of my fully loaded trailer (CAT scale weight), this amount is consistent with the chart from Sailun, and if I understand you correctly, consistent with what you are saying also...true?
This is basically what the industry standard says about replacement tires. If they are the same basic size the tire placard is still correct. However, with a higher load range you have the option of adding inflation pressure to gain load capacity reserves above the LRE tire. By the same I mean something like a ST235/80R16E that provides a maximum of 3520# at 80 PSI. The ST235/80R16G will provide the same amount as the LRE when inflated to 80 PSI.

Plus sizing is another upgrade and the one that gives most people trouble. The same standards applie. The replacement tire must provide (via inflation) a load capacity equal to, or greater than, what the OE tire provided at the recommended inflation pressure found on the tire placard. Because inflation charts will not work with any other sized tire, NHTSA has approved the use of an auxiliary tire placard. The information used to set the recommended inflation pressure for the plus sized tire and the tire size need to be displayed on the auxiliary tire placard (home made). It should be placed adjacent to the original - unobstructed - tire placard. A savvy retail tire installer will do that and also make a note in the vehicle owner's manual. (Reference provided via PM on request).

Most will ask, why is recommended tire inflation pressure necessary? Because the entire automotive industry in the USA revolves around the need to know what the safe pressure is. Many that have trucking experience get confused. That's because that industry operates under a completely different governing body, the Federal Motor Carrier Safety Association, FMCSA. They do not have recommended inflation pressures. They inflate to the load carried - minimum. But, a tire is a tire and their tires cannot be inflated beyond their maximum load capacity.
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Old 11-20-2017, 07:42 PM   #27
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Desert185, who did you spray chemtrails for? I spent 7 years flying RJ's for ASA and finally bailed out of that mess and went 91 corporate. Enjoying life once again!
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I retired from a major, brown, package carrier before going to NASA, who didnít care about age like another government entity. Now, I just fly spam cans.
It sounds like there might be a good story here, but for those of us who don't speak flyboy, could you translate into English?
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Old 11-20-2017, 08:09 PM   #28
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Originally Posted by CWtheMan View Post
This is basically what the industry standard says about replacement tires. If they are the same basic size the tire placard is still correct. However, with a higher load range you have the option of adding inflation pressure to gain load capacity reserves above the LRE tire. By the same I mean something like a ST235/80R16E that provides a maximum of 3520# at 80 PSI. The ST235/80R16G will provide the same amount as the LRE when inflated to 80 PSI.

Plus sizing is another upgrade and the one that gives most people trouble. The same standards applie. The replacement tire must provide (via inflation) a load capacity equal to, or greater than, what the OE tire provided at the recommended inflation pressure found on the tire placard. Because inflation charts will not work with any other sized tire, NHTSA has approved the use of an auxiliary tire placard. The information used to set the recommended inflation pressure for the plus sized tire and the tire size need to be displayed on the auxiliary tire placard (home made). It should be placed adjacent to the original - unobstructed - tire placard. A savvy retail tire installer will do that and also make a note in the vehicle owner's manual. (Reference provided via PM on request).

Most will ask, why is recommended tire inflation pressure necessary? Because the entire automotive industry in the USA revolves around the need to know what the safe pressure is. Many that have trucking experience get confused. That's because that industry operates under a completely different governing body, the Federal Motor Carrier Safety Association, FMCSA. They do not have recommended inflation pressures. They inflate to the load carried - minimum. But, a tire is a tire and their tires cannot be inflated beyond their maximum load capacity.
great info, thanks CW!
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Old 11-21-2017, 02:55 AM   #29
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Willie, when someone refers to "Spam cans" think Cessna 172-182, V-tailed Bonanza, etc. It refers to most any small aluminum aircraft, usually for personal use.
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Old 11-21-2017, 01:30 PM   #30
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It sounds like there might be a good story here, but for those of us who don't speak flyboy, could you translate into English?
What part do you need decoded?
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