I replaced my OEM Westlake 235/80/R16's with Carlisle CSL16 235/85R16's on my 2021 381m.
My old tires had a maximum load rating of 4,080lb at 110psi and the new ones 4,400lb at 110psi.
I would think that I should lower the cold psi to match load ratings; otherwise, I will have an overinflated wear pattern and an unnecessarily stiffer ride.
I called Grand Design with a different question, but ended up asking the tech on the phone about whether I should stick to the PSI on the trailer's sticker or match load ratings. He said the sticker applies if you have OEM tires, otherwise he agrees it would be a good idea to match load ratings.
Unfortunately, Carlisle does not put out a chart for load rating by PSI, and when I contacted them, they said they only test and recommend max psi on their tires. I did find load ratings by psi for other tires in the same class, which all seem to match with each other so I think it is probably a pretty standardized thing. For example here is one for Sailun tires:
https://fifthwheelst.com/documents/Copy of Load and Inflation All ST-Modified.pdf
It shows that for me to match my old tires load rating I should be at 100 psi.
Is there any reason not to lower my psi to 105? I don't actually care about the wear pattern since I will likely age out of tires before wearing them out. Here are my main reasons:
1. It can get to 120 degrees here and the tires can occasionally get super hot on the sun's side (I've seen 130+). Lower PSI can keep the hot temps below 130 (which is what they are rated to).
2. On longer trips, because of temperature and pressure swings, it can get annoying to fill and drain 6 tires every night/morning. If I set it at 105, I have a bigger buffer, where 110 is still fine, and maybe something like 102 is still fine as well.
What do you guys think?
EDIT: For reference, I don't even run my trailer at max weight anyways. I'm usually around 19k out of 20k.
My old tires had a maximum load rating of 4,080lb at 110psi and the new ones 4,400lb at 110psi.
I would think that I should lower the cold psi to match load ratings; otherwise, I will have an overinflated wear pattern and an unnecessarily stiffer ride.
I called Grand Design with a different question, but ended up asking the tech on the phone about whether I should stick to the PSI on the trailer's sticker or match load ratings. He said the sticker applies if you have OEM tires, otherwise he agrees it would be a good idea to match load ratings.
Unfortunately, Carlisle does not put out a chart for load rating by PSI, and when I contacted them, they said they only test and recommend max psi on their tires. I did find load ratings by psi for other tires in the same class, which all seem to match with each other so I think it is probably a pretty standardized thing. For example here is one for Sailun tires:
https://fifthwheelst.com/documents/Copy of Load and Inflation All ST-Modified.pdf
It shows that for me to match my old tires load rating I should be at 100 psi.
Is there any reason not to lower my psi to 105? I don't actually care about the wear pattern since I will likely age out of tires before wearing them out. Here are my main reasons:
1. It can get to 120 degrees here and the tires can occasionally get super hot on the sun's side (I've seen 130+). Lower PSI can keep the hot temps below 130 (which is what they are rated to).
2. On longer trips, because of temperature and pressure swings, it can get annoying to fill and drain 6 tires every night/morning. If I set it at 105, I have a bigger buffer, where 110 is still fine, and maybe something like 102 is still fine as well.
What do you guys think?
EDIT: For reference, I don't even run my trailer at max weight anyways. I'm usually around 19k out of 20k.
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