Mazda 6 Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
393 Posts
Discussion Starter #1
Stock the MS6 comes with a 215/45/18 93Y. Is that the lowest load index rating I should put on it? Would a 91 be no good? Thanks!
 

·
Registered
Joined
·
393 Posts
Discussion Starter #3
Why, what size are you considering as a replacement?
[/b]
I'm looking at some 225/45/18 91Y's
 

·
Registered
Joined
·
2,883 Posts
I'm looking at some 225/45/18 91Y's
[/b]
understand there are two types of load rated tires: xl for rated loads at 41 psi, and sl for rated load at 35 psi.

ms6 oem spec is 93xl at 38 psi. 93xl max capacity is 1433 lbs at 41 psi. At the 38 psi pressure spec, pmetric type (p215, p225) xl tires are downrated to about 1360 lbs, the mazda implied required load rating.

91xl tires are rated at a maximum of 1356 lbs, but need to be at 41 psi ... a bit rough.

if sl (standard vs extra load ) tires are used 91sl tires are rated at maximum of 1356 lbs at 35 psi, so they would work at lower than spec pressure.

check potential tires for xl vs sl ratings. most oem size are xl, but some 225-45-18 are available in sl.
 

·
Registered
Joined
·
393 Posts
Discussion Starter #5
Hmm, I think I'm getting it now. :) The OEM are 93xl and the ones I'm looking at are 91sl. So, if I'm understanding this right, I'd be ok with the 91sl's right?
 

·
Registered
Joined
·
2,767 Posts
I'm looking at some 225/45/18 91Y's
[/b]
That size is available in XL (95 load index), if you desired. But if you do go with the 91, make sure you have at least 35 psi (which actually gives you the same load capacity, 1312 lbs, as the 215/45R18 93 at 38 psi).
 

·
Registered
Joined
·
2,883 Posts
That size is available in XL (95 load index), if you desired. But if you do go with the 91, make sure you have at least 35 psi (which actually gives you the same load capacity, 1312 lbs, as the 215/45R18 93 at 38 psi).
[/b]
If it's pmetric (not on toyo web charts), 91sl is 1356 capacity at 35 psi, matching derated oem at 38 psi. pressure corrections are different for pmetric.
 
1 - 7 of 7 Posts
Top