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Old 02-10-2019, 12:12 PM   #1
River Duck
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8 ply or 10 ply?

Looking to replace the goodride 8 ply that came on our fifth wheel when we bought it new. Going with the Carlisle 225 75 r15. Max loaded weight of the trailer is 10,500 lbs.

Would it be best to bump up to a 10 ply or is there a reason(air pressure increase, wheels, axles etc.) I need to stay with 8 ply? I know tires are a crucial component, wanna make sure I get it right. Thanks in advance
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Old 02-10-2019, 12:30 PM   #2
busterbrown
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I would suggest going up to the highest load range for that size tire, which is an LRE. You'll gain nearly 300 lbs of reserve capacity per tire.
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Old 02-10-2019, 01:05 PM   #3
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I don't disagree with going to LRE, but you only gain the capacity if the wheels are rated for the LRE weight and air pressure as well. The wheel (rim) will have a max weight and air pressure allowed. Only as good as the weakest link.
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Old 02-10-2019, 01:17 PM   #4
River Duck
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Originally Posted by Wxman View Post
I don't disagree with going to LRE, but you only gain the capacity if the wheels are rated for the LRE weight and air pressure as well. The wheel (rim) will have a max weight and air pressure allowed. Only as good as the weakest link.
This was the exact reason I felt the need to ask on here. I thought the wheel would have a stamp on it somewhere about pressure limits but I couldn’t find it. Looked on the backside of it and read through the owners manual. Nothing
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Old 02-10-2019, 01:26 PM   #5
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If it didn't have a max pressure stamp, did it have a max weight stamp on the wheel? If the max weight was up to the LRE weight, or more, I believe the max pressure is 'automatically' up to the corresponding LRE pressure. Metal valve stems above 65psi is the standard for most. Mine have a weight stamp only that I can't read without removing the wheel.
Good luck
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Old 02-10-2019, 01:33 PM   #6
River Duck
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Originally Posted by Wxman View Post
If it didn't have a max pressure stamp, did it have a max weight stamp on the wheel? If the max weight was up to the LRE weight, or more, I believe the max pressure is 'automatically' up to the corresponding LRE pressure. Metal valve stems above 65psi is the standard for most. Mine have a weight stamp only that I can't read without removing the wheel.
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Good point. I’ll check for a weight stamp the next chance I get. I know it had some stamping on the backside, just nothing about pressure. Had to lay down underneath to look.
Already bought some metal stems. Some of the cheapest insurance available if you ask me.
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Old 02-10-2019, 01:39 PM   #7
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When contemplating increasing the load capacity of the replacement tires the limiting factor is the wheels PSI limit. Some of their manufacturers rate them with max load capacity and a PSI limit. Others just rate them for the load they can carry which includes the PSI necessary to carry that load.

When the trailer manufacturer selected the wheels and OE tires for your trailer it was for their ability to carry the maximum load of the GAWRs. The GAWRs have not changed so the wheels are good to go as long as they are rated for the increased PSI. The valve stems could very well be rated for 65 PSI and would have to be replaced. Steel valve stems are the best replacements.

The extra load capacity the new tires will provide is; “load capacity reserves”. It’s one of the best durability factors one can purchase with replacement tires.
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Old 02-10-2019, 02:12 PM   #8
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Quote:
Originally Posted by River Duck View Post
This was the exact reason I felt the need to ask on here. I thought the wheel would have a stamp on it somewhere about pressure limits but I couldn’t find it. Looked on the backside of it and read through the owners manual. Nothing
If you have the aluminum wheels (I believe you do), the back should have similar cast markings to these photos. If you have steel wheels, then you'll need to find some identifying info and look them up on the manufacturer's website.

If yours are aluminum there are two "lug patterns" for the casting, the 5 lug wheels are rated at 2150 and 6 lug wheels rated at 2830. The pressure ratings for these wheels equate to the load range for the tire sizes mounted on the wheel. 5 lug=2015= 205 75R15 LRD= 50PSI and in 6 lug rating, = 2830=225 75R15 LRE= 80PSI.

So, essentially, the casting is rated to carry 80 PSI, but the tires mounted on the casting drilled with 5 lug holes can only support 50 PSI...

Anyway, here's the photo of the information cast in the back side of your aluminum wheels.
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Old 02-10-2019, 03:21 PM   #9
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I think that during times when the weather outside is nasty, folks have a tendency to overthink things. Get the 10 ply LRE. They are stouter tires regardless. Has anyone ever heard of a wheel blowing up? Will lawyers haunt your doorstep if you put LRE tires on your trailer? I have had LRE tires on my steel rims for years and not once have they blown up. The tires on my TV have a much higher load rating the the OEM and the truck rims have yet to blow up.
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Old 02-14-2019, 07:45 PM   #10
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I think that during times when the weather outside is nasty, folks have a tendency to overthink things. Get the 10 ply LRE. They are stouter tires regardless. Has anyone ever heard of a wheel blowing up? Will lawyers haunt your doorstep if you put LRE tires on your trailer? I have had LRE tires on my steel rims for years and not once have they blown up. The tires on my TV have a much higher load rating the the OEM and the truck rims have yet to blow up.

Switching from LR-D to LR-E and not increaseinginflation above 65 psi will gain you nothing but a lighter wallet.
It is the air pressure that supports the load. If you look at the Load tables for tires you will only see increased load capacity when the inflation increases when dealing with tires of the same size.
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