Hey guys, I have a mid 1990's Coleman tent trailer that I tow for camping in the summers. It's a single axle, and a relatively light trailer (2 double beds that pull out). What PSI would you guys recommend running the trailer tires at? They say 75psi MAX Cold. I've been running them at around 50psi, maybe even a little more, and I've been having problems with tire blow outs on long trips. I don't know if the PSI is the problem. A young guy at a service shop said I should be running them like car tires, in the 30s. Help?

 

Most trailer tires are designed to operate at max pressure. That would be 75 pounds when cold in your case. I am presuming you have an "ST" tire on there.

You could also look at the make and model and look them up on the manufacture's web site.

 

Blowouts are an indication of heat build up caused by too low a pressure. Get them higher. Also if they are starting to dry rot, which they will over time, may cause blow outs.

PS, if the guy at the service shop thinks you should be running your truck tires at 30, he is an idiot.

 

I've been having blow out problems for a while now, so the two tires on the trailer are new, within the last couple years. Should I up the pressure to the recommended MAX COLD inflation pressure printed on the tire? 75psi? It makes sense that a low pressure causes more sidewall flex and more friction heat resulting in a blow out. How long should a trailer tire last with proper settings?

 

Always run trailer-rated tires at the max cold. They will dry rot long before they are worn out. I would recommend replacing the wheel and tire assembly due to corrosion issues with the wheels.

 

One thing I see a lot on trailers is incorrect valve stems placed in the wheels.
Before you inflate your tires to max air pressurfe make sure your tire valve can take the pressure.

All rubber valve stems have a maximum pressure rating of 45-65PSI and if you inflate these higher this could be the cause of the blow out instead of a tire failure. (These are by far the most common in cars and trailer tires.)
Like these:
http://www.priertiresupply.com/index...S&Category=218

Brass/rubber high pressure valve stems have a maximum pressure rating of 65-85PSI (can be identified by a brass shaft between the cap and rubber base)
Like these:
https://www.blackjacktirerepair.com/index.asp?pchild=7

Brass or Steel valve stems have pressure rating up to 150PSI
Like these:
https://www.blackjacktirerepair.com/index.asp?pchild=25

The downside to everyone using brass or steel valve stems is cost and they have a tendency to leak more so than a rubber valve stem.

 

I have rubber valve stems. So according to that I'm limited to 65psi maximum in my tires even though people are saying I need to inflate up to the max cold pressure of 75psi?

 

Some of the all rubber are limited to 45PSI depending on manufacturer.
As a good rule of thumb you shouldn't inflate over 45PSI on rubber valve stems unless you know the manufacturer's rating.

 

So I guess my tires and valve stems are mismatched. Why would the tire shop sell me tires that need 75psi in them and put valve stems only rated to 45psi? Do most light trailer tires for things like tent trailers come with brass valve stems? I've only seen rubber ones on the trailers I've hauled.

 

Most trailer manufacturers order tire/rims to install on their trailers. They buy them cheap and in bulk. The tire shop has no idea the end product the tires will be used on. It is the job of the manufacturer to spec out what they want/need/ can afford.

Like I stated.. rubber valve stems are commonly installed.... but because cost is/was $0.02-0.04 each
High pressure stems cost $0.12-0.35 each

Most tire installers are kids who have no idea.
they just do what they are told.

Why I know??
14 years owning/operating tire stores before moving into the trailer industry.

I was a supplier for a few trailer manufactuer's tire/wheel needs. They all asked for cheapest.

Think the trailer manufacturer's know what they are doing??
Then why are there so many trailers that are not even DOT compliant for lighting and brakes??
Some are the king of cheap.

 

Not to steal your tunder but I have a light (290lbs) load rite motorcycle trailer that I use to pull my motorcycle or atv with that weighs no more than 450lbs. My max tire pressure is 80psi but I've been running 70psi. Is this good or bad. Should I inflate to 80? I've pulled my atv twice from NYC to NC and back.

 

Look at the rating for that pressure on the tire. It may not be as high as you think. That rating x 2 is the max trailer/load weight you can carry, although I would not max them out.

 

You could do what I did. When I read this info in a prior Colorado Osprey post. I toke these 2 trailer tires in and had Hi-pressure valve stems added. Not worth taking a chance. I put pressure at max as listed on sidewall.
It would be a good idea to weight trailer when packed for travel. You may be surprised.

 

I would always use the maximum cold pressure allowed by the tire rating. Most ST trailer tires are C, D, or E rated. C is a maximum 50 PSI tire, D & E are higher. One thing that hasn't been mentioned yet is the speed at which you are towing. ST tires, if you have them, are only rated for 65 mph. If you are towing at 70 to 80 mph on a hot day, expect trouble. It is all about heat build-up. That is why you want the maximum pressure allowed to minimize sidewall flex; therefore heat. And of course your speed.