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Old 10-10-2019, 01:55 PM   #61
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There is a difference between maximum(allowed) cold pressure and what most think is max pressure, pressure written behind AT on sidewall, or belonging to loadrange.

The pressure behind AT, will call it AT- pressure furtheron, is the pressure for wich the maxload is determined, for a speed , mostly max speed of tire, but not always.

The maximum cold pressure, is the maximum cold the tiremaker allowes.

The rising of pressure by higher temp in tire is all calculated in in the system, so no problem if pressure rises by driving .

Once read from one of the specialists here, that teststandards are used in tire-desighn, that they have to stand a pressure of 2 to 3 times the AT-pressure. This is for a AT 80 psi tire 160 to 240 psi!!!!!!

In earlyer days tiremakers allowed higher then AT , but nowadays not anymore.

But this all tells us, that you easyly can smuggle a bit with that AT pressure, if needed for laws of nature. Only dont do that with an already damaged tire by overheating , by using to low pressure for the load on tire,only once, then the mechanical forces that tear the beginning cracks furter, only get larger, and tire will fail sooner, and high pressure is blamed.
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Old 10-10-2019, 02:56 PM   #62
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Location: Taylors, SC
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Tire inflation pressures: There has to be a right way. Who defines the right way? Cold is cold. NHTSA defines cold tire inflation to be performed when the tires are cold,

If the vehicle has been setting in a covered garage for three hours, the tires are cold. If the vehicle has been parked at a campground at the Salton Sea for three hours, the tires are cold. If the vehicle is parked at Lake Tahoe for three hours, the tires are cold.

If the tires do not qualify for cold because they haven't set for three hours and you think the tires need inflation. Inflate them to the placard recommended inflation pressures. Later on, when the vehicle has had a chance to set for three hours, reset the inflation pressures.
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Old 10-10-2019, 05:19 PM   #63
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A couple of months ago I bought a Cougar xlite 21RGS which has the original tires 225/75R/15D on it (date code 2013). I put it away for the winter but will replace with E rated tires in the spring before we use it again. Talking to Discount Tire they tell me that they don’t even stock the D’s since all they ever do is use the E’s. They recommended the 80 PSI and I would think going form an 8 ply (D) to a 10 ply (E) would be a benefit too. I asked whether the wheels are okay going to E’s and he didn’t think twice about saying it’d work. Is this sound right?
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Old 10-10-2019, 05:48 PM   #64
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With the size of your trailer I would sure check behind the wheels and see what they are rated for before upping to 80 psi. I am assuming you are meaning 21 RBS? With 2013 tires I would be in the tire store before I did anything else with the trailer as far as going anywhere.
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Old 10-10-2019, 06:07 PM   #65
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Yes, 21RBS. I always thought the 5 year rule was crap and now I know better thanks to this forum. Like I mentioned I’ll put new tires on in the spring before we use it. I didn’t feel the need to buy new tires and let it sit there all winter.
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