Blowout/Tire Separation

[MrGallegos]

Originally Posted by Bill

Conventional wisdom - including from tire experts - says that 5 years is about all you can expect from trailer tires. Appearance doesn't matter, and it is common for good-looking tires to fail. Just ask me - I have done it several times.

I would suggest that you rummage around the Internet for info specific to trailer tires. Roger Marble is a good source, since he has no ax to grind. By contrast, tire manufacturers will either tell you that their tires last a long time or avoid avoid the issue entirely - they want you to buy their tires. And tire shops may overhype the problem, for the same reason - they want you to buy new tires from them.

So take my comments with a grain of salt - but do your own research to confirm or deny it.

Bill

Thanks, looks like a lot of good information to go over and consider, plus he has some informative links like this one https://www.rvsafety.com/rveducation...-tire-pressure

So if I read this correctly, even if we have PSI at the max level for the tire, it may actually be over-inflated if the trailer is empty or lightly loaded. Thus it seems what is needed is a table to determine what PSI to use based on the load, such as one for traveling with the trailer completely empty, such as taking it for repairs and one for a fully loaded camping trip.

[ShrimpBurrito]

If the tire is inflated only to the max pressure for which the tire is rated, the tire is not overinflated, and I don't think you're at any increased risk of tire failure. You might, though, start noticing there's a high spot on the tread, as evidenced by the center of the tread wearing faster than other parts of the tread.

The more immediate issue with having a tire that is inflated way beyond what is necessary to support the load is that the ride will be rougher. In a TM, that means things everything gets jostled around more. If you're not on particularly rough roads, that may just mean that screws come lose over time. But if you hit some nasty bumps or potholes, things might happen faster, so the oven might pull out from its mount, the wardrobe might rip out of where it's attached, etc.

I often travel on rough roads, and so for main interstate travel, I find my load range E rated tires do great at 65 psi. I might even get away with 60 psi. Their max psi is 80, and that definitely resulted in too rough a ride.

Dave

[Bill]

Originally Posted by MrGallegos

... it seems what is needed is a table to determine what PSI to use based on the load, such as one for traveling with the trailer completely empty, such as taking it for repairs and one for a fully loaded camping trip.

I wouldn't try to get too picky or too exact about tire pressure. Trying to tweak it would be a wasted effort. After all, the tire will heat up considerably as you drive, which means the pressure will change by several psi, sometimes by many psi. The amount of heating, and therefore the amount of pressure change, will depend on whether it is a hot day or a cool day, whether you are driving on asphalt (black) or concrete (light color) and even which tire is on the sunny side of the trailer and which is on the shady side. All of these things are out of your control, so trying compensate for them is not possible, and not needed.

These are a few rules of thumb for tire pressure.
1. Under-pressure is VERY destructive to tires, and almost guarantees a failure. Over-pressure may result in a bit more tread wear in the center, but is otherwise harmless unless you air them up way beyond the sidewall rating.
2. Air up your tires first thing in the morning, before any heating has occurred, and then leave them alone! Do not let air out of a tire to reduce the pressure caused by heating. The tire designers have taken this heating into account as part of the design.
3. Fourteen inch trailer tires (load range C) are almost always rated for 50 psi max pressure and 1870 pounds weight max at 50 psi. On a TM, they don't have much margin, so always air them up to 50 psi.
4. Fifteen inch tires may be load range D (65 psi max) or load range E (80 psi max). As Dave said, you would probably want to run both kinds at 60 psi (TM lightly loaded) or 65 psi (heavily loaded). Stay within that range.

FWIW, I finally broke down and got a TPMS a year ago, and watched the readings. I was surprised to see that when I started the day at 63 psi, the pressure quickly rose to 68-70 psi, and sometimes maxed out the reporting capability of the TPMS (72 psi) on a hot day with a loaded TM. I also saw that the difference sunny-side to shady-side was usually 3 or 4 psi on a sunny day.

Bottom line. Choose an initial pressure for the kind of run you expect to make that day. Air up the tires to that number, and leave them alone. If you don't want to spring for a TPMS, get a simple tire pressure gauge, and check them a couple times during the day. At every stop, I make it a practice to put my hand on the sidewall of the tire and feel for badly increased temperature, a sign of under-inflation that should be dealt with promptly.

Sorry such a long post, but after a lot of experience (good and bad), and a lot of actions (smart and stupid), it seems to work. It won't make things perfect, but it will help.

Bill

[Bill]

I was reminded of a follow-up topic. It is interesting to go online and find a load table for your particular tires. Each tire brand will have one somewhere. It is important to realize what may be obvious - the load table tells you the absolute max load for the tire at a given pressure, not the recommended load. You should always leave some margin.

Bill