trailer tires?

[roscoe]

Suggest you find and re read those directions to see if they aren't talking about max load. If so, you're right. Partial load is what I'm talking about. This is nothing new, and it's common knowledge. Check into it.

Well, I suggest you find and discard that wives tale.
Every tire retailer says to run ST tires at max pressure.
Do I need to provide 3-4-5 links for you, no.
Tire manufacturers say the same thing.
The last three sets of trailer tires I purchased, ( Karrier, Kenda, and Carlisle) had a sticker on the tire, or accompanying literature with tire that stated to run at max pressure.
And then there are the dozens of members here, and hundreds of tire shops that say the same thing.


While I have seen one (1) tire manufacturer that has a tire load/air pressure chart on their website, it is there to show the decreased capacity of the tire as pressure drops, not to recommend you use lower air pressure.


Loadstar/Kenda:
"Trailer tire manufacturers always recommend running the max air pressure that is specified on the side wall (measured when the tires are cold)."


ETrailer:
"Special trailer tires should be inflated to their maximum air pressure. At the maximum air pressure, the tires will perform and wear best, and get the best gas mileage."


Carlisle:
"Tire Inflation
"Always keep the tire manufacturer's maximum recommended air pressure in all your trailer tires."
– Maintain air pressure at the maximum PSI recommended on the tire sidewall.


Karavan Trailers:
"What tire pressure should I inflate to?
You should always maintain your tires at full pressure. This is indicated by the tire manufacturer on the tire's sidewalls or on the trailer manufacturer's certification label. Always check tire air pressure when the tires are cold."

Yes, this is a seriously contested subject, even here on iboats. Imagine that. Synthetic, solder, crimp.
But not a single person has cited a manufacturer's source that says to lower your air pressure for a lighter load.
While anecdotal evidence and pleas by some to "use common sense" are all nice, they don't change the facts.


Question: Do you know any commercial carriers or professional drivers, that change the air pressure based on their load? 3 pallets of eggs, or a 30,000# coil, the air pressure stays the same.

And if lowering the air pressure is what we are supposed to do, where is this documented?
Where is the online calculator?
Where is the easy to use app for your phone?


As you said, " Check into it. "

endtrans

 

[bigdee]

Well, I suggest you find and discard that wives tale.
Every tire retailer says to run ST tires at max pressure.
Do I need to provide 3-4-5 links for you, no.
Tire manufacturers say the same thing.
The last three sets of trailer tires I purchased, ( Karrier, Kenda, and Carlisle) had a sticker on the tire, or accompanying literature with tire that stated to run at max pressure.
And then there are the dozens of members here, and hundreds of tire shops that say the same thing.


While I have seen one (1) tire manufacturer that has a tire load/air pressure chart on their website, it is there to show the decreased capacity of the tire as pressure drops, not to recommend you use lower air pressure.


Loadstar/Kenda:
"Trailer tire manufacturers always recommend running the max air pressure that is specified on the side wall (measured when the tires are cold)."


********:
"Special trailer tires should be inflated to their maximum air pressure. At the maximum air pressure, the tires will perform and wear best, and get the best gas mileage."


Carlisle:
"Tire Inflation
"Always keep the tire manufacturer's maximum recommended air pressure in all your trailer tires."
– Maintain air pressure at the maximum PSI recommended on the tire sidewall.


Karavan Trailers:
"What tire pressure should I inflate to?
You should always maintain your tires at full pressure. This is indicated by the tire manufacturer on the tire's sidewalls or on the trailer manufacturer's certification label. Always check tire air pressure when the tires are cold."

Yes, this is a seriously contested subject, even here on iboats. Imagine that. Synthetic, solder, crimp.
But not a single person has cited a manufacturer's source that says to lower your air pressure for a lighter load.
While anecdotal evidence and pleas by some to "use common sense" are all nice, they don't change the facts.


Question: Do you know any commercial carriers or professional drivers, that change the air pressure based on their load? 3 pallets of eggs, or a 30,000# coil, the air pressure stays the same.

And if lowering the air pressure is what we are supposed to do, where is this documented?
Where is the online calculator?
Where is the easy to use app for your phone?


As you said, " Check into it. "

endtrans

Thank you Roscoe. I have been pounding that into peoples minds for years. Air pressure is what gives tires integrity,period,end of sentence. Trailers are about hauling a load not passengers so comfort should be of no concern. If your boat can handle cross wakes and chop it can definitely handle a trailer ride. The springs are there to cushion the load....not the tires. Shocks can be added to trailers which would solve the issue but how many trailers have you ever seen with shocks? Have you ever ridden in the back of an 18 wheeler like the one that delivers new boats to dealers.

 

[ahicks]

Because the majority of my experience was as a service manager at a larger RV dealership (20 years), that ended 30 years ago. So I did look into it (to see if there's been a change), and I did learn something. It's about the tires with "ST" in the size. Those actually are recommended to run at max rated, no matter the load, and that's due to the side wall construction being heavier than other more conventional tires. They say they overheat when allowed to flex.

This pretty much justifies my habit of feeling/checking the sidewall temps with my hand after having traveled a few miles. I do the same on the hub to check bearing temps while I'm at it - for the same reason. Those will not let go unless they're overheated either!

Anyway, I spend a good deal of time with a partially loaded utility trailer behind me lately, in my travels as a retiree who likes working on dead outboards as a hobby, and as a snowbird commuting between Florida and Michigan on a regular basis. I can tell you for sure the trailer is set up for 3000 lbs max, but seldom has much more than 6 or 700lbs in it. The tires ARE ST rated. I do adjust tire pressure for the load, as I do not care for this trailer bouncing around in back of my SUV, or rattling my brains out, when tires are inflated with 3 times the air they need to do their job.

In my 50+ years of trailering all over God's creation, I have never blown a tire, or burnt out a bearing. Not once. I give the majority of the credit for that to the fact I check the tire and hub temps religiously. It takes all of 2 seconds.... FWIW.

Oh, BTW, semi tires are run at max as they never know what's going to be in them next - if anything.

 

[82rude]

Point for me is I will be carrying the same load all the time with the trailer tires that were from the factory in size and load rating C.Both rv center and tire mfg say 80psi so 80psi cold it is.ahicks you may have just cursed yourself in bragging about never having a blowout or bearing failure,lol.Me,ive found if you never want to ever have a hub failure just buy a spare one and put it in the truck and viola never an issue ever

 

[H20Rat]

The springs are there to cushion the load....not the tires.

If that were true we wouldn't have tires with air in them on trailers. They would be solid or steel core. But yet, we have fragile air filled tires, because they are part of the suspension.

 

[H20Rat]

Can't believe this devolved into a trailer tire psi argument, so here is my $.02... Since many/most of our tires are bias ply, take a tire off your trailer and roll it through a puddle. See the mark it leaves on the ground? Very, very little tread is touching, it is operating WAY outside its intended envelope. The same thing happens if you are running a tire at max PSI but with a light load. The bias ply tire needs to have a certain footprint, and that is achieved with the combination of load and PSI.

The reason SOME manufacturers tell you max PSI is that it is easier to avoid lawsuits that way, and if it wears out the tire faster, the manufacturer wins anyway. Other manufacturers will actually give you charts that show you what PSI you should be running for a specific tire and load.

https://www.maxxis.com/trailer/trailer-tire-loadinflation-chart

 

[H20Rat]

Because the majority of my experience was as a service manager at a larger RV dealership (20 years), that ended 30 years ago.

To be brutally honest, that practice ended probably 30 years ago... If a dealer did that to me today, I would never be back... Every major RV manufacturer and RV tire manufacturer recommends an entirely different practice. They ALL recommend running the tires to max PSI, loading it up 'wet', and then finding the nearest Cat scale. They all have a load chart to follow based on the real world weight.

https://www.thefitrv.com/rv-tips/how...re-in-your-rv/

https://www.michelinrvtires.com/refe...tion-tables/#/

 

[ahicks]

Smokingcrater, when doing my "ST" tire research the other day, I was looking at 12" ST rated tires. I didn't see one where the manf. did not recommend running them at max rated psi. - and yes I did look into several.

That was all news to me, and resulted in post #23.

I have always run tire pressure according to load, and will likely continue to do so.

And I'm not arguing. I'm discussing, exchanging thoughts with others, with the idea of learning something new today!

 

[bruceb58]

Well, I suggest you find and discard that wives tale.
Every tire retailer says to run ST tires at max pressure.
Do I need to provide 3-4-5 links for you, no.
Tire manufacturers say the same thing.

Probably the two best ST trailer tires you can buy right now both recommend pressure vs load

https://www.maxxis.com/trailer/trail...nflation-chart

https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf

Trailer tires are designed to take some of the the shock due to the less sophisticated and less travel suspension. That is one of the reasons trailer tires have stiffer sidewalls. It's also the reason you have to derate a P or LT tire when used on a trailer by 10%.

I also use a TPMS now which will warn you if you pick up a nail and one of your tires start leaking. It also senses temperature:
https://www.technorv.com/tst-cap-sys...to-12-sensors/

 

[82rude]

Chated with the seller and they recommended 80 psi for my application so that's where I go.

 

[bruceb58]

Tip: if it says max load at 50 psi on the sidewall, put about 45 psi in each tire....when they heat up on the highway they can become overinflated and the tread can fail....don't ask me how I know about this, but Walmart gave me no satisfaction on this at all....

The pressure you inflate the tire to is the cold temperature inflation spec. The tire is designed to withstand the pressure increase when the temperature increases.

 

[bruceb58]

Chated with the seller and they recommended 80 psi for my application so that's where I go.

While you are at it, check the max pressure rating of your rim when they mount the tire. I really doubt your rim is even rated for that high of a pressure. Even the 15" rims I bought when I upgraded from 14" to 15" aren't rated higher than 70PSI.

 

[82rude]

FOR what its worth I was just reading the rim psi is dependent on the valve stem pressure rating.If they were selling rims and tires that were not able to handle the specified psi they would be in serious legal trouble id think.Also load range .B is max 60 psi C is max 80psi.

 

[bruceb58]

FOR what its worth I was just reading the rim psi is dependent on the valve stem pressure rating.If they were selling rims and tires that were not able to handle the specified psi they would be in serious legal trouble id think.Also load range .B is max 60 psi C is max 80psi.

Nope..It's independent.

Most load range C tires are 50 and E are 80. Probably different in those small tires you are buying.

If it's a rim tire combo you are buying, yes the rating should be correct if the tire is rated for 80 PSI.

 

[82rude]

This thread started with me looking for 12 inch tires.yes I bought a combo and yes they are load range c 80 psi cold air pressure.My truck tire are 10ply load range e at max load 80psi.My tires were direct replacements for what I had on there same exact size .530x12 load range c .All small trailer tires are b at 60 psi and c is 80 psi .When I say small I mean 12 and smaller .Seems when you go 13 and above they rate them differently .Heres an interesting explanation for larger tires .https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=55

 

[ahicks]

Speaking of rim pressure ratings, I found the 5 hole 12" wheels were rated for higher psi than the 4 hole as well. Something to keep in mind maybe - like when looking at something used, or even when something comes up and you need to replace the hubs.

Thinking my next trailer is going to have 13" 5 hole wheels on it. I think that will give me the flexibility I might be after when it comes to available tire selections.

Love these forums. Learn something new every day!

 

[robert graham]

Why would you under inflate your tires? Isn't the PSI listed on the tire the cold pressure?


OTE=robert graham;n10567503]Tip: if it says max load at 50 psi on the sidewall, put about 45 psi in each tire....when they heat up on the highway they can become overinflated and the tread can fail....don't ask me how I know about this, but Walmart gave me no satisfaction on this at all....

[/QUOTE]

I put the max at 50 PSI and drove to Florida and back....chunks of rubber coming off center of tire treads all the way around, both tires....Walmart said they had gotten hot on interstate and overinflated, causing chunks of rubber coming off....no warranty relief at all.....I'm not sure I believe this story of theirs and I'm not happy with their trailer tires, so I got some other tires from a different source, put in 45 PSI (5 lbs below max.)....been running them a couple of years now with no problems...Still not happy with Walmart!....

 

[bruceb58]

Walmart said....

LOL....that's all I had to hear.

 

[bigdee]

For what it is worth. I have ran all my trailers at max psi for 50 years and never had a blowout or horror story. Seen many trailers in construction that had tire failure due to under-inflation.

 

[bigdee]

If that were true we wouldn't have tires with air in them on trailers. They would be solid or steel core. But yet, we have fragile air filled tires, because they are part of the suspension.

Ever pull a trailer with a solid axle (no springs