Goodyear Endurance

[zuley]

A question for the experts if I may. Read here last week that Goodyear has come out with a new made in North America trailer tire. Talked to my tire guy this morning and sure enough he has them on order scheduled for delivery mid March. My concern that I addressed with him is the 225 75 15 Endurance is a 80 psi rated tire where as the aluminum rims on my 2013 Passport Elite 23RB are only rated for 65 psi. He said to go with those tires and keep them at 65 psi. I've dealt with this guy for years, in fact our auto dealership is his biggest customer. We probably buy 2 dozen tires a week off him. I do not believe Mike would mislead me but I am concerned with heat build up running the tires at lower than specified inflation. What are the thoughts from others out there. BTW he quoted me a buck and a quarter each installed which I thought was pretty good.

[66joej]

I think running at 65# versus 80# would cause excessive heat buildup. My tire guy who was in the business all his working life would never recommend running trailer tires at anything other than what stamped on the sidewall. JMO

[sourdough]

My first thought was do you need the increased carrying capacity the 80psi will bring? With the 23RB I doubt you do. In that case I think you can run the new tires at the 65 psi with no problem. You won't have the increased weight capacity but you will have a new, hopefully dependable, tire on the trailer. Just because it is rated for 80psi doesn't mean you have to run it 80 psi. JMO

Note: If I recall what is stamped on the sidewall is "maximum inflated pressure". I don't know if it is different for ST tires (I've never seen it) but you don't have to run any other tire I've had at max pressure.

[slow]

Zuley, take a second look at the backside of your wheels on the spoke. My 2015 23RB has 2830 lbs molded into them which equates to 80 psi with the 225 75 15. I suspect yours is the same.

Here is the web page for my wheels (T03-56655BM) as a second point of reference:
http://sendelwheel.com/wheels/t03bm.html

As for heat build up, it is the flex of the sidewall that generates heat as I understand it. So if this is true, a E tire at 65 psi "should not" heat up any more since the flex "should not" be anymore than a D tire at 65 psi. But, I have been wrong before. Hopefully CW adds to this thread.

BTW: my plan is to get E Maxxis this spring and run them somewhere between 65 and 70 psi depending on wear pattern that develops.

[bartbill]

Slow,

How did you convert 2830 pounds to 80 psi (the math).

[slow]

Slow,

How did you convert 2830 pounds to 80 psi (the math).



I used the Maxxis tire pressure / load chart on their website.

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


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[Tbos]

Look your rims up on line to verify the max pressure you can use. My 2810 has steel rims and the OEM tires were max at 50. I checked with the rim manufacturer and they were rated to 65. I bought new tires that max is 65.


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[JRTJH]

As a "general rule" with aluminum 15" rims, you'll find two numbers stamped in the spokes on the back side of the wheel. One is for "5 lug castings" and one is for "6 lug castings". The actual wheel is the same, but the weight rating corresponds to the weight ratings of the LRD tires and LRE tires that are typically installed on them. The weight ratings are based on a specific pressure requirement, so the wheel has to be rated to carry at least that amount of pressure. My guess is (you can call customer support at the wheel manufacturer to verify this) that the casting is rated at the PSI of the highest weight rating, which in the case of my wheels, is 80 PSI.

In the picture, you can see (I hope) the data. 5H-114.3 MAX LOAD 2150LBS followed by 6H-189.7 MAX LOAD 2830LBS. This corresponds to the load ratings found in ST Tire Load/Pressure Charts. 205 75R15 LRD is 2105 at 65PSI on a 5 lug wheel and 225 75R15 LRE is 2830 at 80 PSI on a 6 lug wheel.

The difference in wheel load rating is based on the number of lugs. Here's a picture of what I'm talking about...

I hope it helps clear things up rather than make them more confusing....

[hdxbonez]

FWIW, the door sticker on my truck tells me to run my 80psi rated tires at 65psi when they're mounted on the front and 80 psi when they're mounted on the rear. I guess Chrysler isn't concerned about overheating them...:popcorn:

If it were me, and my max trailer weight was well under the capacity of the tires, I wouldn't worry about running a lower tire pressure

[CWtheMan]

A load range “D” tire that is the same physical size as a load range “E” tire uses the same load inflation table. Hence, the LRE tire is essentially the same tire as the LRD with an extra 2 ply rating, which allows it to hold the 80 PSI necessary to gain its maximum load capacity rating.

IMO using the LRE tire inflated to 65 PSI to achieve a LRD rating, provides you with nothing more than any other LRD tire.

Rims are certified by SAE to a load capacity and an inflation pressure capacity. Take a look at the specs on the rims in the reference below as an example.

When in doubt, call or email the rim manufacturer for conformation.

http://sendelwheel.com/wheels/s62.html

[hdxbonez]

IMO using the LRE tire inflated to 65 PSI to achieve a LRD rating, provides you with nothing more than any other LRD tire.


Except in the case of the Goodyear. It gives you the ability to run an American, made in the USA, tire in that size.....

[CWtheMan]

FWIW, the door sticker on my truck tells me to run my 80psi rated tires at 65psi when they're mounted on the front and 80 psi when they're mounted on the rear. I guess Chrysler isn't concerned about overheating them...:popcorn:

If it were me, and my max trailer weight was well under the capacity of the tires, I wouldn't worry about running a lower tire pressure

The fitment procedures for automotive tires are not the same as RV trailer tires (any design). Tires fitted to automotive vehicles must provide load capacity reserves. Tires fitted to trailer axles do not have that requirement.

[hdxbonez]

The fitment procedures for automotive tires are not the same as RV trailer tires (any design). Tires fitted to automotive vehicles must provide load capacity reserves. Tires fitted to trailer axles do not have that requirement.

Correct, but this specific discussion was about an underloaded condition, wasn't it?

[sourdough]

A load range “D” tire that is the same physical size as a load range “E” tire uses the same load inflation table. Hence, the LRE tire is essentially the same tire as the LRD with an extra 2 ply rating, which allows it to hold the 80 PSI necessary to gain its maximum load capacity rating.

IMO using the LRE tire inflated to 65 PSI to achieve a LRD rating, provides you with nothing more than any other LRD tire.

Rims are certified by SAE to a load capacity and an inflation pressure capacity. Take a look at the specs on the rims in the reference below as an example.

When in doubt, call or email the rim manufacturer for conformation.

http://sendelwheel.com/wheels/s62.html

The OP was asking about using an LRE tire vs LRD but being limited to 65 psi if the wheels wouldn't support 80 psi. I agree that the LRE would be the same as an LRD at the 65 psi, but, the LRE is rated 10 ply and the LRD is rated 8 ply. Does that not equate to a "stouter" tire even when running 65 psi? Plus, he was looking at going to a new, American made tire so in my mind he would be upgrading from where he is and the LRE would be an upgrade over the LRD.....wrong?

[CWtheMan]

The OP was asking about using an LRE tire vs LRD but being limited to 65 psi if the wheels wouldn't support 80 psi. I agree that the LRE would be the same as an LRD at the 65 psi, but, the LRE is rated 10 ply and the LRD is rated 8 ply. Does that not equate to a "stouter" tire even when running 65 psi? Plus, he was looking at going to a new, American made tire so in my mind he would be upgrading from where he is and the LRE would be an upgrade over the LRD.....wrong?

First, there is no rule stopping someone from using tires of the same size with a higher load capacity than the ones they are replacing, as long as they do not exceed the cold maximum pressure the rim is designed to support.

Tire durability is often confused with tire strength. Tires of the same physical size (ST225/75R15) provide the same load capacity at an equal inflation pressure. In other words, a LRD or LRE will provide 2540# of load capacity at 65 PSI.

[sourdough]

First, there is no rule stopping someone from using tires of the same size with a higher load capacity than the ones they are replacing, as long as they do not exceed the cold maximum pressure the rim is designed to support.

Tire durability is often confused with tire strength. Tires of the same physical size (ST225/75R15) provide the same load capacity at an equal inflation pressure. In other words, a LRD or LRE will provide 2540# of load capacity at 65 PSI.


I agree completely. My thought (and understanding the last many decades) is that a higher ply rating ie: 10 ply vs 8 ply, also indicated a more robust construction of the tire which then enabled it to carry a higher pressure rating. Wouldn't that "robustness" then translate to a "stronger" tire in its construction regardless of tire pressure/weight rating??

[JRTJH]

sourdough,

I think along the same thought process as you.

My understanding comes from and is based on the "old bias ply numerical truck tire load rating/inflation charts", back when we used to weigh each axle and adjust PSI to the actual load that was on the tire. So, yes, the heavier construction of the LRE tire would be more robust, built heavier (it even weighs several pounds more than the LRD tire in the same size) and it would be sturdier, but the actual "certified rating" would be the same at lower pressures. In other words, even though it's a "beefier tire" it hasn't been subjected to testing to specifically rate it (certify it) to be "better than" the D series tire at the same PSI. So to "shortcut" the process the load chart for LRB, LRC, LRD and LRE are all "combined" for a specific tire size, and as the pressure/ply rating increases, so does the load rating, up to the highest PSI rating which is "last certification for that specific ply rating".

What goes up, also goes down, so a LRE is also "rated to carry the load" of an LRD, LRC and LRB tire of the same size at the load ratings those tires are certified to carry when inflated at the PSI for that lower load rating. It would seem (at least to me) that the LRE tire "ought to carry more weight" at 65 PSI than the LRD at that pressure because it's a more robust tire, but it's not "certified or tested" to carry more, so it's "rated" the same at that pressure...

The same applies to a LRC tire at LRB pressure, a LRD tire at LRC or LRB pressure....

Now I think I've even confused myself :banghead:

[sourdough]

sourdough,

I think along the same thought process as you.

My understanding comes from and is based on the "old bias ply numerical truck tire load rating/inflation charts", back when we used to weigh each axle and adjust PSI to the actual load that was on the tire. So, yes, the heavier construction of the LRE tire would be more robust, built heavier (it even weighs several pounds more than the LRD tire in the same size) and it would be sturdier, but the actual "certified rating" would be the same at lower pressures. In other words, even though it's a "beefier tire" it hasn't been subjected to testing to specifically rate it (certify it) to be "better than" the D series tire at the same PSI. So to "shortcut" the process the load chart for LRB, LRC, LRD and LRE are all "combined" for a specific tire size, and as the pressure/ply rating increases, so does the load rating, up to the highest PSI rating which is "last certification for that specific ply rating".

What goes up, also goes down, so a LRE is also "rated to carry the load" of an LRD, LRC and LRB tire of the same size at the load ratings those tires are certified to carry when inflated at the PSI for that lower load rating. It would seem (at least to me) that the LRE tire "ought to carry more weight" at 65 PSI than the LRD at that pressure because it's a more robust tire, but it's not "certified or tested" to carry more, so it's "rated" the same at that pressure...

The same applies to a LRC tire at LRB pressure, a LRD tire at LRC or LRB pressure....

Now I think I've even confused myself :banghead:

John, I agree:facepalm: I'm absolutely positive that the requirements for a 10 ply has to give it more strength than an 8 ply; I've dealt with a family that has owned my tire store for 4 decades and they all have preached ply rating - weight carried is one consideration, but, they are stronger built tires regardless of the tire pressure carried. As I posted (somewhere) when a 10 ply tire weighs 10-15lbs more than an 8 ply...do you not have a stouter tire?
Now it's time to :hide:

[JRTJH]

...Now it's time to :hide:

Not a bad idea to hide... Mind if I join you? ROFL :hide:

[CWtheMan]

I agree completely. My thought (and understanding the last many decades) is that a higher ply rating ie: 10 ply vs 8 ply, also indicated a more robust construction of the tire which then enabled it to carry a higher pressure rating. Wouldn't that "robustness" then translate to a "stronger" tire in its construction regardless of tire pressure/weight rating??

It would seem so. The problem is, tire industry standards are not about "what ifs". They are about factual, usable, equations. Tire manufacturers submit their findings to the Tire & Rim Association for standardization. The end result is tire inflation tables/charts. Durability is not a strength test. However, it can determine a tire's life expectancy, to some degree. It has a lot to do with brand "X" is better than brand "Y". Word of mouth will have a lot to do with that outcome, if there is a clear one.

Do sidewall inserts make the tire's sidewall stronger? Do taller, more densely packed tread compounds add strength to the carcass? Do more ply cords add physical strength to the carcass? They are all unmeasured variables. Does adding an extra steel belt designed to help prevent carcass penetration damage add load capacity strength? In the end, what we have to work with is on the tire's sidewall information and in the tables/charts provided by the tire industry.

Here is some of the hype about the new Endurance. "The tire's internal structure includes twin steel belts with a two-ply nylon reinforcement to stabilize the tread, increasing traction and durability. The Endurance features a polyester cord body to help smooth out the trailer's ride, and a scuff guard is molded into the sidewall to further increase durability by resisting damage from contact with curbs during parking lot maneuvers."

Maybe that will provide a longer lasting tire. But, if it's not properly maintained it will just be another Marathon by another name.

[sourdough]

It would seem so. The problem is, tire industry standards are not about "what ifs". They are about factual, usable, equations. Tire manufacturers submit their findings to the Tire & Rim Association for standardization. The end result is tire inflation tables/charts. Durability is not a strength test. However, it can determine a tire's life expectancy, to some degree. It has a lot to do with brand "X" is better than brand "Y". Word of mouth will have a lot to do with that outcome, if there is a clear one.

Do sidewall inserts make the tire's sidewall stronger? Do taller, more densely packed tread compounds add strength to the carcass? Do more ply cords add physical strength to the carcass? They are all unmeasured variables. Does adding an extra steel belt designed to help prevent carcass penetration damage add load capacity strength? In the end, what we have to work with is on the tire's sidewall information and in the tables/charts provided by the tire industry.

Here is some of the hype about the new Endurance. "The tire's internal structure includes twin steel belts with a two-ply nylon reinforcement to stabilize the tread, increasing traction and durability. The Endurance features a polyester cord body to help smooth out the trailer's ride, and a scuff guard is molded into the sidewall to further increase durability by resisting damage from contact with curbs during parking lot maneuvers."

Maybe that will provide a longer lasting tire. But, if it's not properly maintained it will just be another Marathon by another name.

Thanks CW. I'm of the mind that the higher ply rating equals a "stouter" tire IMO. Life is too short to get involved in complicated "stuff". BTW I love your contributions

[zuley]

Thank you every body. Lots information here to digest. Lively debate certainly certainly gets the brain function operating. I've got about 6 weeks before I need to decide anything. Keep the conversation going. Unlike the Trump verses Clinton debate I'm enjoying this one. :-)

[CWtheMan]

Thank you every body. Lots information here to digest. Lively debate certainly certainly gets the brain function operating. I've got about 6 weeks before I need to decide anything. Keep the conversation going. Unlike the Trump verses Clinton debate I'm enjoying this one. :-)

I looked at the specs for your 2013 model trailer. Keystone went overboard with extra load capacity for your Original Equipment tires - listed on the specs as ST225/75R15D. My guess is your GAWR axles are rated at 3200# ea. That means the OE tires provide more than 1700# of load capacity reserves at 65 PSI for each tire position. No need to upgrade, just use new tires of the same size that you have confidence in.

You can verify the figures on the trailer's certification label located on the LH forward external section of the trailer. If you're unsure what to look for here is a picture of a certification label & tire placard I took at a RV show. Notice the trailer is larger than yours and has smaller tires.

http://www.irv2.com/photopost/showfull.php?photo=27431

[slow]

............ My guess is your GAWR axles are rated at 3200# ea. ..........[/url]

They are 4400# each.

Axles, tires and wheels are all overkill on the 23RB. But I am not complaining.

[kksfish]

JRTJH.....nice explanation and photo! I gotta check my wheels and see if mine are the same rating

[srvnt]

Ordered a set of 4 of the new Goodyear Endurance from America's Tire. 5 to 7 days to ship to my local AT, coming from Texas. Should have a new manufacturing date. Made in USA. I'm going to have them balance them also along with new metal stems installed.