Trailer tire pressure

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raycarlson
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Re: Trailer tire pressure

Post by raycarlson » Wed Oct 15, 2014 12:23 pm

1.Low pressure only causes heat if there is excessive sidewall flex, a 'D' range tire(65psi,2500#) with only 1000# load will NOT have excessive sidewall flex even at 35psi.temps are easy to check with nice new little temp guns, no guessing or approximating, you can do your own exact temp-pressure tests in a one-hour interstate drive and prove-disprove any preconceived guesses you now have, internet 0pinions do not need to be trusted any longer, it's to easy to perform your own tests.
2.This tire expiration due to age is nothing but a gimmick to scare the unknowing into purchasing more tires needlessly. If you know what to look for when inspecting a tire you can easily tell if you might be running an unsafe tire. The tire industry started the "must use st trailer" tires 20 years ago to sell extra unneeded tires and generate more income when all that really matters is the load rating, regular tires worked fine for 60years as long as they matched the load. Now starting this year I have noticed Discount Tire is picked up on this scare tactic with passenger cars telling the gullible housewives they need to replace the tires on their little grocery getters every five years. Boy profits will really be going up now, Funny nowhere will you see any government or traffic safety organization preaching this info, only the tire industry. If there was any actual truth to the rumor there would be mandatory legislation requiring tire replacement. Remember how fast tire pressure monitoring systems were mandated in all vehicles after a few fatal wrecks in overloaded minivans with under inflated tires. If age expired tires were really a problem safety wise you can count on some type of regulation would be mandated already. Best action is to learn what your looking at when inspecting your tires.

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Re: Trailer tire pressure

Post by kmclemore » Wed Oct 15, 2014 1:09 pm

Ray, I do agree that tire date codes can be misleading - if a tire is properly stored it can last longer than the code would indicate. And I also agree that there are certain signs that you can see to clue you in that a tire is beyond it's safe use date, cracking sidewalls being the most evident. However, there are a few things you cannot see, and chief among these is the hardening of the rubber itself. This hardening can cause a tire to skid far more easily and become quite dangerous, particularly in the wet.

kurz
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Re: Trailer tire pressure

Post by kurz » Wed Oct 15, 2014 3:15 pm

What do you think about this formula?

maxPressure of tire / maxLoad of tire * actual load of tire

Will look at my tire next time and will calculate some examples!

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Crikey
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Re: Trailer tire pressure

Post by Crikey » Wed Oct 15, 2014 8:20 pm

Just an aside: Wouldn't you think those automotive super thin 'all rim' tires would have almost no sidewall flex?
I wonder how my stock MacGregor selections stack up against good current market types?

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Re: Trailer tire pressure

Post by seahouse » Thu Oct 16, 2014 12:46 am

kurz wrote:What do you think about this formula?

maxPressure of tire / maxLoad of tire * actual load of tire

Will look at my tire next time and will calculate some examples!
There are charts already made, such as this one Kurz...

http://www.maxxis.com/trailer/trailer-t ... tion-chart

Note that this doesn't hold for auto tires at high speeds, like in Europe. Both summer and winter tires for my sedan have a max pressure of 51 psi stamped on them, while the automaker says 30 psi front and rear. There are many variables, but at high sustained speed the cold tire pressure needs to be adjusted up, but at those elevated speeds and increased pressures the load rating actually goes DOWN! (a bit).

I suspect that ( still referencing autos) between 35 and up there would be no significant increase in the tire's load rating (because it's already at its maximum), but the range between 35 and 51 is used to play with handling and performance characteristics other than load rating, that depend on the application and circumstances.

- B. :wink:

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dlandersson
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Re: Trailer tire pressure

Post by dlandersson » Thu Oct 16, 2014 5:30 am

Dude, I wanna put "rims" on my Mac trailer. With LED lights, etc. It's be, like, fer sher, so the "bomb", totally rad. :P
Crikey wrote:Just an aside: Wouldn't you think those automotive super thin 'all rim' tires would have almost no sidewall flex?
I wonder how my stock MacGregor selections stack up against good current market types?

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Re: Trailer tire pressure

Post by Crikey » Thu Oct 16, 2014 8:45 am

dlandersson wrote:Dude, I wanna put "rims" on my Mac trailer. With LED lights, etc. It's be, like, fer sher, so the "bomb", totally rad. :P
Crikey wrote:Just an aside: Wouldn't you think those automotive super thin 'all rim' tires would have almost no sidewall flex?
I wonder how my stock MacGregor selections stack up against good current market types?
Well not quite. :? It was just an idea... :D :D

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dlandersson
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Re: Trailer tire pressure

Post by dlandersson » Thu Oct 16, 2014 4:22 pm

And a good one...I like rims. See below, Chris Rock :)

https://www.youtube.com/watch?v=zZYryyA28go
Crikey wrote:
dlandersson wrote:Dude, I wanna put "rims" on my Mac trailer. With LED lights, etc. It's be, like, fer sher, so the "bomb", totally rad. :P
Crikey wrote:Just an aside: Wouldn't you think those automotive super thin 'all rim' tires would have almost no sidewall flex?
I wonder how my stock MacGregor selections stack up against good current market types?
Well not quite. :? It was just an idea... :D :D

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Re: Trailer tire pressure

Post by Crikey » Fri Oct 17, 2014 9:05 am

Hahahaha! :D

Those tiny tire profiles must have zero forgiveness when it comes to curbs and potholes. Do they carry higher pressure ratings?
If I was driving a 350 (something) with the dual's on the rear I could probably get away with twinning up the trailer end as well and avoid the extra expense of another axle. I've followed people that have trailers so big that they take up an entire lane width.

R.

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Re: Trailer tire pressure

Post by Hugh » Tue Jun 09, 2015 8:30 pm

This thread seems to have been wandering :wink:
:macm: aluminum trailer single axle 60 ETEC
Weight approx 4400# I think

I run ST225/75D215 Carlyle tires rated on the sidewall, just as the Maxis website says, at 2450# @ 65psi
I've been inflating to 55#. Trailer tracks well even in sidewinds as I encountered today coming into the Mountains on TCH #1 towards Canmore AB. I started looking for more info because I really could not remember what pressure I should be using and found this thread.
Using a cheapo handheld infrared gauge the hubs were both at 44C after I backed into my driveway, after 1/2h of 100kph (62 mph)

It appears to me that I'm doing this right.

Hugh

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Re: Trailer tire pressure

Post by raycarlson » Wed Jun 10, 2015 8:22 am

With a single axle you are at max load rating already, definitely you should run the sidewall recommended 65psi inflation pressure for safety sake. running underinflated was referring to dual axle trailers that had a total tire capacity of 10,000 pounds because of having four tires. the temperature of your hubs have nothing whatsoever to due with tire sidewall flex overheating to failure. we were referring to the actual temp of the tire sidewall not axle hubs. this is why the manufactureres puts labels recommending loads and pressures, for people who don't really know what their doing, it keeps them from hurting themselves or others.

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Re: Trailer tire pressure

Post by Catigale » Wed Jun 10, 2015 11:36 am

I put the tires at maximum sidewall pressure on my single axle stock :macx: trailer.

I also throw the tires away after 5 years. My goal is to never change a tire on the roadside.

Small boat tires have a 10 year life in my house, then they get moved to spares.

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Re: Trailer tire pressure

Post by Retcoastie » Thu Jun 11, 2015 8:41 am

There is an answer to the tire pressure question per each manufacturer. It is/was hard to come by.

You have all seen the pictures of tires showing different types of wear. One shows an over inflated tire with the center of the tread worn. Another shows an under inflated tire with the outsides worn. Somewhere in between then must be the proper inflation pressure. Back in the day when I was towing travel trailers, when it came time to purchase new tires, I would call the manufacturer. After talking to sales people who didn't have a clue what the proper pressure should be, I would keep after them until they would put me thru to an engineer. Engineers are nice people and I would get them to send me a chart of what they felt was the proper pressure should be for each weight. Then weigh each tire, adjust each tire and problem solved. The trick was getting that chart.

Now, I'm lazy and don't make the effort any more. I just look at max pressure, add about 4, and let it go. This produces a very harsh rides and really shakes up the trailer contents. The shock load on the trailer is huge. So much so that after increasing to Load Range D tires, the next trip one wheel sheared all the lug studs and departed the trailer. It could have been the numerous salt water immersions. It could be old age. It could be bad driver. Or it could be shock load. At any rate, I changed the remaining lug studs to be safe.

An interesting side note. My towing insurance company could not find anyone who would pick up the boat on the road. With one wheel on the ground, no rollback could pick it up without dragging the stern on the pavement. I spent the night on the side of the interstate until they returned the next day to repair it on the side of the road.

Ken

raycarlson
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Re: Trailer tire pressure

Post by raycarlson » Fri Jun 12, 2015 9:25 am

No engineer needed he has already stamped the info on the sidewall, thats all anyone needs.............4psi overinflated would in noway play a part in fracturing 5 lugs all at once, sounds more like a serious maintenence problem or lack of knowledge..

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Re: Trailer tire pressure

Post by BOAT » Fri Jun 12, 2015 10:37 am

kmclemore wrote:Ray, I do agree that tire date codes can be misleading - if a tire is properly stored it can last longer than the code would indicate. . .

Yeah! I eat food after the expiration date all the time! Those dates are just to scare you into buying more food and tires! I only get sick like once a month so that prooveds the dates are misleading! :P

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