Forum Discussion
BenK
Aug 12, 2013Explorer
There are several classes of tires in discussion so far...here they
are and the rest of them
'ST' class, or trailer tires and not to be used on vehicles carrying passengers
Next higher class is 'P', or passenger car tires and when used on light duty
trucks (pickups and SUV's) must be derated a min of 9% from that tires sidewall
rating. Folks used to argue and even called me a lier when first came here over
12 years ago, but most tire sites (TireRack is the main source for folks here)
started to quote the RMA (rubber manufacturer Association) recommendations of
that (another thing folks don't seem to understand here is that when an OEM
'recommends' something and you didn't follow that recommendation...that OEM
most likely will deny warranty due you ignoring their recommendation)
Next higher class is 'LT', or light truck tires
Next higher class is 'Commercial', or semi truck tires
Next higher class is 'off road', or those +8 foot dia tires. Some weigh several
tons EACH
When changing class of tire from that vehicles (including trailers) OEM recommendation,
is to Re-Engineer that tire/suspension. Ditto when changing tire sizes from
the OEM recommended. Ditto changing wheel sizes/spec from what came from the OEM
Personally do NOT like ST class tires and my trailers all had converted to LT
class tires with wider wheels to make those LT tire sidewalls behave 'stiffer'
Careful on 'one load range higher', as if the discussion is with ply's, then
out of context without the tires size. Example is a LT245/75R16 load range E
(10 ply rating) might have lower capacity than a 285/75R16 load range D (6 ply
rating)
are and the rest of them
'ST' class, or trailer tires and not to be used on vehicles carrying passengers
Next higher class is 'P', or passenger car tires and when used on light duty
trucks (pickups and SUV's) must be derated a min of 9% from that tires sidewall
rating. Folks used to argue and even called me a lier when first came here over
12 years ago, but most tire sites (TireRack is the main source for folks here)
started to quote the RMA (rubber manufacturer Association) recommendations of
that (another thing folks don't seem to understand here is that when an OEM
'recommends' something and you didn't follow that recommendation...that OEM
most likely will deny warranty due you ignoring their recommendation)
Next higher class is 'LT', or light truck tires
Next higher class is 'Commercial', or semi truck tires
Next higher class is 'off road', or those +8 foot dia tires. Some weigh several
tons EACH
When changing class of tire from that vehicles (including trailers) OEM recommendation,
is to Re-Engineer that tire/suspension. Ditto when changing tire sizes from
the OEM recommended. Ditto changing wheel sizes/spec from what came from the OEM
Personally do NOT like ST class tires and my trailers all had converted to LT
class tires with wider wheels to make those LT tire sidewalls behave 'stiffer'
Careful on 'one load range higher', as if the discussion is with ply's, then
out of context without the tires size. Example is a LT245/75R16 load range E
(10 ply rating) might have lower capacity than a 285/75R16 load range D (6 ply
rating)
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