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Old 09-06-2017, 06:27 AM   #22
Desert185
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Join Date: Jul 2014
Location: Nevada
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Quote:
Originally Posted by JRTJH View Post
If you consider the aging of the polyester cording I think you'll answer your question. "Larger size polyester" is used in ST tires to give them the extra load capacity over LT tires. The polyester weakens as it ages. Estimates are 10% per year. So, tires size 235 80R16 LRE are rated at 3520 pounds at 80PSI. The 326SRX and 326SRXWE don't weigh the same, so taking the heavier of the two, the 326SRX at 9745 with a payload of 2915 and a pin weight (empty) of 2260 (23% of 9745), if we calculate the GVW pin weight the same 23%, that would be 12560x.23=2889. So 12560-2889=9671 (on the axles) divided by 4 tires would mean 2418 on each tire at GVW.

With 3520 rated capacity and 2418 actual weight, that's 1102 reserve per tire. That's roughly 31% reserve capacity on "new" tires. Given the 10% aging degredation of the polyester cording, at the end of 3 years the tires would be carrying roughly their "maximum aged rating". So, just for grins, at 6 years (60% reduction) the tires would have a capacity of 3520x.40=1408 pounds each. That's 5632 max tire capacity with 9671 on the axles.

Maxxis may have a limited warranty against some loss, but from the 10% age reduction, I'd be concerned at the end of the 3rd year from the date of manufacture.

Plus, to "add insult to injury", this is included in the Maxxis warranty CW posted: "(C) Loss of time, inconvenience, loss of use of the trailer, costs of towing or transportation, and/or incidental or consequential damages of any type or nature. Vehicle or trailer damage is not covered."

The two paragraphs above this one are filled with "outs" for the tire company to use to avoid payment for damages. While Maxxis is an "outstanding company" with a superb reputation, who knows what their financial status and policy toward paying for trailer damage will be "if the worst happens in 6 years"...

Just doing the math and knowing the weights we carry, I'd start worrying about tire safety and reliability about the 3 year mark when the tires are "age rated" at the trailer's GVW. I don't think I'd trust 6 years with any brand ST tire in the LRE category.

John:

I knew the answer before I asked the question. I just wanted to hear CW's response/recommendation...and still do.

Sorry you responded in such a thoroughly accurate manner, but I'm sure someone will benefit from your detailed posting on this subject as I already have in the past since joining this forum.

The Maxxis 235/80R16 LRE tire loading is 3420#, BTW. 100# less than the same tire in a Carlisle, which didn't concern me at the time of purchase because of the good history of the tire and the axle loading of the 326SRX. With current knowledge of the Carlisle HD's, along with the price point compared to the Maxxis, the Carlisle HD will be my next tire at year four in the spring of 2018.

One could also argue than the 326 is lighter than the 325 because of the dinette and extra wall enclosing it in the 325. My advertised 326 EW is 9300# and change with a GW of 12,600# on 5,200# axles. I like the 6,000# axle upgrade Bobby posted.

One of these days, I'll weigh the trailer when I'm in the mood to handle the truth.
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Desert185 🇺🇸 (Retired Chemtrail vendor)
-Ram 2500 QC, LB, 4x4, Cummins HO/exhaust brake, 6-speed stick.
-Andersen Ultimate 24K 5er Hitch.
-2014 Cougar 326SRX, Maxxis tires w/TPMS, wet bolts, two 6v batts.
-Four Wheel 8' Popup Camper.
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