Correct inflation of trailer tires

Keep in mind that - if you have a dual axle trailer - and you have a blowout on one tire, the ENTIRE weight previously being carried by two tires are suddenly going to put on the single remaining tire. A good argument for seeing to it that each tire can handle the maximum amount of weight they are capable of.

On my trailer I keep my ST tires at the max. When I’m fully loaded I’m covered and if I’m less than full load the only downside is possible irregular wear. I’d rather have enough air pressure to cover the possibility of being heavy.

I too have been rolling for 30 + years. Always run max pressure in the trailer tires. I currently run 110 in the OR but those tires are G rated. Served me well.

Another thought. Under inflated trailer tires can add to sway because with the reduced pressure. The sidewalls flex more allowing the trailer to rock more side to side. This side to side movement while the tire is spinning continually stretches and relaxes the sidewalls which is what causes the sidewalls to heat up.

When not moving side to side this same action occurs under the weight of the trailer because the tire is also flatter where it contacts the road and rounder where it doesn't adding to heating as well. Being flatter where contacting the road occurs whether under inflated or not, but is much worse when under inflated.

When filled to the max psi the sidewalls stay stiffer and don't allow the continuous cycle of stretching and relaxing to occur as badly. It also reduces the amount of rocking from side to side that can occur caused by the sidewalls flexing.

The downside is the trailer can have a bumpy ride when going down the road. But you don't ride inside the trailer anyway and why you should secure items inside the trailer.

The comments above are addressing ST trailer tires only and why they should be inflated to their max psi. The compounds are different than those used in car tires and light truck tires because the nature of the needs for trailer usage. Trailer tires also sit for a long time in between trips.

Car and light truck tires however are designed for day-to-day usage and to flex more than trailer tires creating a smoother ride. So for the most part the heating is not as big a deal as with ST trailer tires. However the side to side movement can still be a problem adding to sway when they are used on a trailer.

Most def. max. sidewall psi unless you're rims can't handle it. The tires will age out long before wearing out. For plenty of great info. on RV tires by a retired tire engineer, visit RVtiresafety.net.

We just got a new set of Endurance tires installed and have them inflated to 80 psi. What I did notice on the sidewall instead of just "max. 80 psi" is that the tires now say "for max. load capacity inflate to 80 psi. Our old tires were Marathon LRD and I kept them inflated to max. sidewall psi of 65 psi at all times. Got 5-1/2 seasons out of them and well over 20K miles.

What you want is a min. of 15% reserve load capacity to reduce the risk of a tire failure. If you previously had LRD tires at 65 psi and had at least 15% reserve capacity, you could reduce the pressure down to 65 psi and get the same load capacity you used to have.

Only have about 50 miles on the Endurance tires so far and can't really tell if there's much of a difference yet. There def. isn't a harsher ride to me, which some say there will be. FWIW, I have the rear tires on our truck at 80 psi rear and 65 front as per the OEM specs.

I'm by no means an expert in this, but it seems to me that uneven tire wear is the major downside to running at full pressure. A rougher ride may be slightly noticeable, and I've never once had a concern with traction. That said, most who tow trailers are towing few enough miles that the tires will age out long before they wear out. For this reason, we tow at full pressure, knowing that our tires will get about 30k miles in the 5 years we own them before replacementy.

BB_TX wrote:
Even tire different manufacturer web sites don’t agree. Some provide recommended tire inflation charts based on loading. And from a maximum rubber to road contact viewpoint, and therefore maximum traction, that certainly makes sense. But it also means you have to know the weight on each tire. Other sites simply say inflate to the max pressure as stated on the sidewall. That is probably the safest approach, and certainly the easiest. Downside is that if the weight on the tire is far less than the max load rating, there would less rubber contact to the road as the tire tread would be more rounded, the tire may wear faster in the center of the tread, and the ride could be harsher due to the tire being harder.

Take your pick.

even some mfg are inconsistent and say inflate to max sidewall in some places and then say use inflation guide in another place for the same exact tire.

Now IMHO if you go from a LRC to a LRE, staying with max inflation may not be necessary or wise, but I went from LRD to LRE and inflate to 80psi rather than the LRD 60 psi.

I have been inflating my trailer tires to the max as indicated on the sidewall for over 30 years and have never had a tire problem. Trailer tires (especially dual axle trailers) are under a lot different conditions than truck or automobile tires. Inflating them to the max makes them more able to withstand the harsh conditions they operate under.
Barney

Even tire different manufacturer web sites don’t agree. Some provide recommended tire inflation charts based on loading. And from a maximum rubber to road contact viewpoint, and therefore maximum traction, that certainly makes sense. But it also means you have to know the weight on each tire. Other sites simply say inflate to the max pressure as stated on the sidewall. That is probably the safest approach, and certainly the easiest. Downside is that if the weight on the tire is far less than the max load rating, there would less rubber contact to the road as the tire tread would be more rounded, the tire may wear faster in the center of the tread, and the ride could be harsher due to the tire being harder.

Take your pick.

Tires disintegrate faster due to heat. Heat occurs when you have flex in your sidewall. Some flex is necessary, but excessive flex leads to increased heat which leads to increased chance of tire failure.

I buy trailer tires that are rated much higher than I need them. Then I keep those tires inflated for their maximum weight carrying capabilities. When I check my tire and hub temps at fuel stops, they are usually just a little hotter than ambient temps. That is my objective.