Load Rating quandary, wheels vs tires!

[Fourdoor]

Hey guys,

This information is pertaining to the MYP, if you have good information on the MY LR or MY AWD (standard range) that differs from this, please add to the data!

For the MYP, the front axle max load rating is 3004 lbs, and the rear axle max load rating is 3306. I am pretty sure (but not 100%) that this is based on the wheel load ratings on the factory 21" wheels. So, if you are going to get aftermarket wheels, and you want to be able to rotate them front to back you have to go with the most restrictive rating which would be for the rear axle, meaning that you have to have a minimum wheel load rating of 1650 lbs. Now, here is the wierd part... the tire load rating is NOT 1650 lbs! Because the MYP is considered and SUV your tire load ratings are reduced to 91% of whatever the load rating is on the tire... so for the MYP you need minimum load rating of 1814 lbs to meet the minimum of 1650 lbs (1814 x .91 = 1651)

Another thing, don't go by the "you have to have XL or HL load rating tires no matter what". Some SL (standard load) tires are just fine. I am looking for some narrow eco focused all season tires for road trips. I found some tires I really like, and was going to not purchase them because they had and SL load rating, but when I looked at the actual numbers, they were rated for 1929 lbs and 51 psi max pressure... well above the rating needed for my MYP. Some other tires I was thinking about (also listed as SL) have a max load rating of 1764 lbs and 51 psi max pressure... those ones I cannot use. The difference? The size! A 235/55/18 standard load is 1764 lbs max load. A 235/60/18 standard load is 1929 lbs!!! Makes ya think don't it?

Keith

PS: Why are wheels not .91% load adjusted but tires are?

 

[jcanoe]

Hey guys,

This information is pertaining to the MYP, if you have good information on the MY LR or MY AWD (standard range) that differs from this, please add to the data!

For the MYP, the front axle max load rating is 3004 lbs, and the rear axle max load rating is 3306. I am pretty sure (but not 100%) that this is based on the wheel load ratings on the factory 21" wheels. So, if you are going to get aftermarket wheels, and you want to be able to rotate them front to back you have to go with the most restrictive rating which would be for the rear axle, meaning that you have to have a minimum wheel load rating of 1650 lbs. Now, here is the wierd part... the tire load rating is NOT 1650 lbs! Because the MYP is considered and SUV your tire load ratings are reduced to 91% of whatever the load rating is on the tire... so for the MYP you need minimum load rating of 1814 lbs to meet the minimum of 1650 lbs (1814 x .91 = 1651)

Another thing, don't go by the "you have to have XL or HL load rating tires no matter what". Some SL (standard load) tires are just fine. I am looking for some narrow eco focused all season tires for road trips. I found some tires I really like, and was going to not purchase them because they had and SL load rating, but when I looked at the actual numbers, they were rated for 1929 lbs and 51 psi max pressure... well above the rating needed for my MYP. Some other tires I was thinking about (also listed as SL) have a max load rating of 1764 lbs and 51 psi max pressure... those ones I cannot use. The difference? The size! A 235/55/18 standard load is 1764 lbs max load. A 235/60/18 standard load is 1929 lbs!!! Makes ya think don't it?

Keith

PS: Why are wheels not .91% load adjusted but tires are?

Perhaps because tire are affected by higher temperatures, leading to tire failure while wheels are not affected by temperature.

 

[Goobers]

Hey guys,

This information is pertaining to the MYP, if you have good information on the MY LR or MY AWD (standard range) that differs from this, please add to the data!

For the MYP, the front axle max load rating is 3004 lbs, and the rear axle max load rating is 3306. I am pretty sure (but not 100%) that this is based on the wheel load ratings on the factory 21" wheels. So, if you are going to get aftermarket wheels, and you want to be able to rotate them front to back you have to go with the most restrictive rating which would be for the rear axle, meaning that you have to have a minimum wheel load rating of 1650 lbs. Now, here is the wierd part... the tire load rating is NOT 1650 lbs! Because the MYP is considered and SUV your tire load ratings are reduced to 91% of whatever the load rating is on the tire... so for the MYP you need minimum load rating of 1814 lbs to meet the minimum of 1650 lbs (1814 x .91 = 1651)

Another thing, don't go by the "you have to have XL or HL load rating tires no matter what". Some SL (standard load) tires are just fine. I am looking for some narrow eco focused all season tires for road trips. I found some tires I really like, and was going to not purchase them because they had and SL load rating, but when I looked at the actual numbers, they were rated for 1929 lbs and 51 psi max pressure... well above the rating needed for my MYP. Some other tires I was thinking about (also listed as SL) have a max load rating of 1764 lbs and 51 psi max pressure... those ones I cannot use. The difference? The size! A 235/55/18 standard load is 1764 lbs max load. A 235/60/18 standard load is 1929 lbs!!! Makes ya think don't it?

Keith

PS: Why are wheels not .91% load adjusted but tires are?

I'm not sure about that whole 91% part (you put .91% at the end, typo?). Could you cite where you got that from?

Because it's an SUV (heavy one at that)? Isn't that why there's an XL rating?

 

[MattM24]

I'm not sure about that whole 91% part (you put .91% at the end, typo?). Could you cite where you got that from?

Because it's an SUV (heavy one at that)? Isn't that why there's an XL rating?

SUVs can be easily overloaded. That’s why the tires have to be able to account for 10% more load.
It’s in the following link somewhere.

https://www.toyotires.ca/sites/default/files/application_of_load_inflation_tables_20170203.pdf

I’m not sure I’d get SL tires, since XL tires typically have more/stronger belts.

 

[Fourdoor]

Perhaps because tire are affected by higher temperatures, leading to tire failure while wheels are not affected by temperature.

That is a good point about wheels not being affected by temperature... the reason given for the 91% rule is that they expect you to do stupid crap like overload the vehicle if you have an SUV or truck. An overloaded wheel will not just fail during normal driving, but is more likely to fail if you hit a pothole or road debris, but the tire doesn't need an external force to fail, just some time to build up heat from being over loaded. I think you might be correct!

Keith

 

[Fourdoor]

I'm not sure about that whole 91% part (you put .91% at the end, typo?). Could you cite where you got that from?

Because it's an SUV (heavy one at that)? Isn't that why there's an XL rating?

Yeah, I was typing fast in the PS and put .91% instead of either x.91 or 91%.

The source of that information is on this page:

The Importance of Load Ratings: The Unsung Hero of Vehicle Safety

The load index of a tire tells you how much weight the tire can carry. Also known as load rating, the load index is represented by a number that’s found on the tire’s sidewall.

www.tirereview.com

Here is the relevant paragraph:

"As a further nuance governing the use of Euro-metric and P-metric sized tires on vans, pickup trucks and SUVs, Bridgestone notes, “Because these vehicles have a higher center of gravity and greater probability of being overloaded than passenger cars, vehicle engineers are required to specify Euro- or P-metric sized tires rated to carry 10% more weight than would be required if they were used on a passenger car…the equivalent of taking the tire’s load capacity branded on its sidewall and multiplying it by 91%. For example, a Euro- or P-metric tire designated to carry 2,000 pounds on a car is restricted to carrying 1,820 pounds when used on a van, pickup truck or SUV.”

Later,

Keith

 

[Fourdoor]

SUVs can be easily overloaded. That’s why the tires have to be able to account for 10% more load.
It’s in the following link somewhere.

https://www.toyotires.ca/sites/default/files/application_of_load_inflation_tables_20170203.pdf

I’m not sure I’d get SL tires, since XL tires typically have more/stronger belts.

If you want to go higher than that, then sure it will be stronger... but a tire in size 235/55/18 XL is rated for 1984 lbs, and a tire in size 235/60/18 SL is rated for 1929 lbs, not that much difference and both of them are well above the required load rating of 1814 lbs. My only beef with the "you have to have XL" statement is that it is not technically true based on going to a slightly different tire size, and it limits peoples options. Using tire rack for example, if I shop for 235/60/18 tires I can get SL or XL and there are 128 choices available. If I shop for 235/55/18, I have to get XL because the SL do not have a high enough load rating, so I am limited to the 29 XL tires they have available to make my selection.

128 tires to chose from vs 29 tires to chose from... and in reality I am willing to use either size, so win win I have 157 to chose from!

Just some food for thought,

Keith