ST vs LT tires.
What is it about this subject that causes threads to close sooooo quickly? The last lasted 8 hours!!! before it was closed. So let's try this again, but folks - let's keep it civil. No name ...
Forum Discussion
FastEagle wrote:
Here is one of the basic reasons the ST tire cannot be compared to the LT tire and vice versa.
The ST235/85R16E has a load capacity of 3640# at 80 psi.
The LT235/85R16E has a load capacity of 3042# at 80 psi.
FastEagle
These 2 tires have the same Load Rating "E" rated. It's right there in the description.
As we know the designators for a tire's "load rating" whether that be C,D or E harkens back to the number of plys in the olden days when we used bias-ply tires.
With todays radial tires the only factor relating to a tires "rating" is it's maximum inflation pressure. C=50PSI, D=65PSI, and E=80PSI
Now they have different maximum load capacities for E-rated ST's and LT's with the same max pressure because ST's and LT's have different standards and testing protocols that they are subject prior to certification since the regulated uses of these 2 tires are different.
One is lawfully never to be used on passenger carrying vehicles and one can be used to carry passengers.
One is restricted to a low maximum speed and the other a substantially higher speed.
Based on these different testing protocols and certification standards for ST and LT tires their resultant load capacities are different.
Both these tires meet any requirement in regulations or recommendations that states replacement tires must meet or exceed original tire "load ratings". Keep in mind that means "max inflation pressure"
I have yet to see wording in any regulation that uses the word "capacities"
As I have said before I would run LT tires at 90-95% of their load capacities all day run over running ST tires at 75-80% of their maximum capacities.
No one has shown any indisputable argument or regulation not to run a ribb'ed closed shoulder tread patterned LT tire whose sum of the load capacities meets or exceeds the maximum axle capacities as an OEM replacement tires.
All we have is corporate legal department butt covering recommendations and private individuals opinions based on their own personal experiences, biases and agendas.
