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Cummins12V98

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Posted: 07/14/21 09:15pm Link  |  Quote  |  Print  |  Notify Moderator

QCMan wrote:

Most chinese tires specify that they should be inflated to max pressure at all loads. If you unmounted one and felt how thin the sidewalls are you would understand why.


Maybe you can post that please.


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Cummins12V98

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Posted: 07/14/21 09:16pm Link  |  Quote  |  Print  |  Notify Moderator

QCMan wrote:

One of the ones that come to mind is Trailer King tires. Molded into he sidewall is "Keep inflated to 80 psi". That is on a 225/75 r15 lre tire. Had 14 inch ones that stated "keep inflated to 65 psi". Tow Masters had similar verbiage.


Please post a pic.

Tal/IL

Central Illinois

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Posted: 07/14/21 09:27pm Link  |  Quote  |  Print  |  Notify Moderator

jjrbus wrote:

Tal/IL wrote:

jjrbus wrote:

So I go and get rig weighted and inflate rear tires to 10% over psi suggested in load and inflation tables.


I DID NOT HAVE A TIRE FAILURE. I keep getting told to run tires at much higher pressure in case I get a blow out, makes no sense.


Your tire failure may have been totally unrelated to air pressure. Still, I am curious: how did "10% over psi suggested in load and inflation tables" compare to sidewall max pressure?


In my mini Toyota sidewall max psi is 65, load and inflation table load range D tire calls for 39 psi, I run 43 and use TPMS.


Sorry, but in my mind a blow-out is a tire failure.

I am always curious about how folks use load/inflation tables. I see a lot of reference to them. I go with the advice of my neighbor, who is maintenance director for a large commercial truck leasing company. He manages the tire program for a fleet of several hundred tractor/trailer units. His advice to me for my motorhomes has always been to inflate to sidewall max pressure and go. Under-inflation equals excessive sidewall flex, equals excessive heat, equals blow-outs.


35 miles from Normal, IL. As close to normal as I'll ever be.

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Sagebrush

Jacksonville AL

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Posted: 07/14/21 09:52pm Link  |  Quote  |  Print  |  Notify Moderator

If they wear okay at max pressure you will be okay, just a harder ride and maybe less traction. I don't run semi truck drives at max pressure ever. Sometimes the steers get max pressure though depending on the tire's load capacity. On the 200 ton and bigger mobile cranes we aired up and down with a CTIS, that was nice to have.

Most of my trailers have Asian tires because of the sizes. I've only lost one 225/75/R15E on the road recently. Its been years since I blew a Chinese 14" tire, I think those have improved actually.

I was blowing apart those Carlisle and Tow King 14" tires yearly for a while back in the late 90's and early 2000's. The E rated ST 15's have been doing better than the D rated for me. The Mastertrack steel belts make a difference in hot weather I think. I'm very careful with air pressure. My E rated 15" trailer tires are rated for 81 mph at 80 psi. Most ST's are only 62 to 65 mph at max pressure. Endurance ST's are rated for 87 mph I think. Good to know your truck tire specs too, I've seen cheap 12R22.5's with 62 mph speed ratings.

* This post was edited 07/14/21 10:00pm by Sagebrush *

Cummins12V98

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Posted: 07/14/21 10:10pm Link  |  Quote  |  Print  |  Notify Moderator

Tal/IL wrote:

jjrbus wrote:

Tal/IL wrote:

jjrbus wrote:

So I go and get rig weighted and inflate rear tires to 10% over psi suggested in load and inflation tables.


I DID NOT HAVE A TIRE FAILURE. I keep getting told to run tires at much higher pressure in case I get a blow out, makes no sense.


Your tire failure may have been totally unrelated to air pressure. Still, I am curious: how did "10% over psi suggested in load and inflation tables" compare to sidewall max pressure?


In my mini Toyota sidewall max psi is 65, load and inflation table load range D tire calls for 39 psi, I run 43 and use TPMS.


Sorry, but in my mind a blow-out is a tire failure.

I am always curious about how folks use load/inflation tables. I see a lot of reference to them. I go with the advice of my neighbor, who is maintenance director for a large commercial truck leasing company. He manages the tire program for a fleet of several hundred tractor/trailer units. His advice to me for my motorhomes has always been to inflate to sidewall max pressure and go. Under-inflation equals excessive sidewall flex, equals excessive heat, equals blow-outs.


Sorry your neighbor is ill informed.

Cummins12V98

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Posted: 07/14/21 10:12pm Link  |  Quote  |  Print  |  Notify Moderator

Sagebrush wrote:

If they wear okay at max pressure you will be okay, just a harder ride and maybe less traction. I don't run semi truck drives at max pressure ever. Sometimes the steers get max pressure though depending on the tire's load capacity. On the 200 ton and bigger mobile cranes we aired up and down with a CTIS, that was nice to have.

Most of my trailers have Asian tires because of the sizes. I've only lost one 225/75/R15E on the road recently. Its been years since I blew a Chinese 14" tire, I think those have improved actually.

I was blowing apart those Carlisle and Tow King 14" tires yearly for a while back in the late 90's and early 2000's. The E rated ST 15's have been doing better than the D rated for me. The Mastertrack steel belts make a difference in hot weather I think. I'm very careful with air pressure. My E rated 15" trailer tires are rated for 81 mph at 80 psi. Most ST's are only 62 to 65 mph at max pressure. Endurance ST's are rated for 87 mph I think. Good to know your truck tire specs too, I've seen cheap 12R22.5's with 62 mph speed ratings.


Re think your 14-16” tire choices with GY ENDURANCE tires.

jjrbus

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Posted: 07/15/21 06:09am Link  |  Quote  |  Print  |  Notify Moderator

Tal/IL wrote:

jjrbus wrote:

Tal/IL wrote:

jjrbus wrote:

So I go and get rig weighted and inflate rear tires to 10% over psi suggested in load and inflation tables.


I DID NOT HAVE A TIRE FAILURE. I keep getting told to run tires at much higher pressure in case I get a blow out, makes no sense.


Your tire failure may have been totally unrelated to air pressure. Still, I am curious: how did "10% over psi suggested in load and inflation tables" compare to sidewall max pressure?


In my mini Toyota sidewall max psi is 65, load and inflation table load range D tire calls for 39 psi, I run 43 and use TPMS.


Sorry, but in my mind a blow-out is a tire failure.

I am always curious about how folks use load/inflation tables. I see a lot of reference to them. I go with the advice of my neighbor, who is maintenance director for a large commercial truck leasing company. He manages the tire program for a fleet of several hundred tractor/trailer units. His advice to me for my motorhomes has always been to inflate to sidewall max pressure and go. Under-inflation equals excessive sidewall flex, equals excessive heat, equals blow-outs.


Everyone has an opinion on psi, even some high end fleet people. Now there is a company that has been in business over 100 years, has billions of miles of tire experience. Bus loads of engineers, truck loads of computers. Access to data and studies from gov, university's around the world. Michelin made a film on how to weight and determine how much psi should be run in tires. Michelin is also financially responsible if the info is wrong. So do I trust Tommy tire the guru or Michelin? I'm going with Michelin!

The argument always is you will get much better mpg with higher pressure. Show me one credible study that shows this. I cannot find one, only that the difference is negligible.

CapriRacer

Somewhere in the US

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Posted: 07/15/21 06:17am Link  |  Quote  |  Print  |  Notify Moderator

Tal/IL wrote:

Sorry, but in my mind a blow-out is a tire failure. .....


Be careful here. Tires can "blow out" due to road hazards. That's not the fault of the tire. It's just one of those things. If you always blame the tire for a blow out, then you'll be trying to fix a problem that doesn't exist. That could get expensive.


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mr_andyj

Georgia

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Posted: 07/15/21 09:38am Link  |  Quote  |  Print  |  Notify Moderator

You said your RV is overloaded 30% but this means nothing to us. How much weight was on that one tire?
Tires have a weight rating.
Running over the weight rating on a tire for a few minutes is not a reason to replace the tire.

How old are the tires?

Inflating 10% over is not going to ever cause a blow out, ever. Never.
Tires are rated at half of their max psi cold. Often on the highway tires will heat up and the psi will increase, way way past your 10% figure, and this is how tires work.
I know this bc a friend worked for a major global tire manufacturer.

Old tires that have not been kept up to normal psi, very old tires, if you increase psi and drive then that is enough to blow the tire out. The wire/nylon radials often will break and the tire shred into pieces when you drive it. I mean maybe a 10+ year old tire that has been sitting at low pressure then aired up and driven on interstate for a while...

If your tire hit a bad pothole just the right way and got damaged then this is the reason for your blowout. Blowouts are not always a sign that the tire was bad to begin with, but typically the tire is partially at fault anyway.
I had a friend that was a really bad driver. Remember the trailer tires site further out than your vehicle tires, so if you miss the pothole on the side of the road your trailer tire might hit it. This friend borrowed my trailer and hit everything on the side of the road. The tires were fine, but I had to replace the bent axle.

Blowouts only indicate that ALL the tires are bad when all the tires are as old as the dead one, over 6 years is old. over 10 is really old, and 20 is going to be a very big problem very soon.

No, driving on a tire overloaded a few minutes is not reason to replace it.

Sagebrush

Jacksonville AL

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Posted: 07/15/21 11:38am Link  |  Quote  |  Print  |  Notify Moderator

Its good to hear the Gooodyear quality control is better now and people like them. I had a bad experience a few years ago with that brand and so did a few of my friends.

If these new trailer tires have issues I might try the Goodyears again. I may not even own this old 2006 trailer in three years, who knows. But its around $350 with tax to put four Mastertrack U203 E's on there right now. If they make it another three to four years I'm good. I have TPMS, so I keep an eye on the temp and psi.

Over inflation is not good, even max psi is too much sometimes. That max psi rating is not a suggestion. Make sure the valve stems are rated for the psi! Most shops use snap in 65 or 80 psi on the 15" or 100 psi rubber stems on the 16". I have to buy my own metal bolt ins and bring them to the shop, around here they never have the bolt in type for small wheels. Mine are rated for 200 psi and they last and last.

* This post was edited 07/15/21 11:45am by Sagebrush *

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