Tire Size

[rdb1125]

I'm driving a 2011 Sierra 2500 HD 4wd crew cab with factory 20" wheels.
The truck came with ""Goodyear SR-A tires LT265 60 R20""

1st question:
I wanted to bump up one tire size, my tire guy tells me he has had some customers have problems with the computers in their vehicle after changing tire size and doesn't reccomend doing it. Has anyone had any issues with this ?

2nd question:
Does anyone else have the same size tire ???
After searching all the major tire brands the only tire I could find that same size is the tire listed above, great tire but I was hoping to find something with a slightly more agressive tread.


Thanks

 

[Z15]

The tire dealer is wise to recommend against it due to possible liability concerns over these issues by the tire and vehicle oem's. By changing one element of a vehicle suspension system, many other elements can be impacted, affecting everything from ride and handling, to safety. A truck that has different size tires and wheels will also have Engine power/performance concerns, Transmission shift concerns, Speedometer registered speed concerns, and Cruise Control concerns.

The Engine Control Unit (ECM) and Transmission Control Module (TCM) use (RPM) and (VSS) inputs as operational parameters for engine torque, transmission shifting, cruise control operation and speedometer indicated vehicle speed. Changing tires size changes these inputs which can cause the vehicle to work harder to overcome these changes.

Larger tires cause more drag (push air), more rolling resistance (pavement friction) and more sprung weight (tires weigh more) all effecting the performance of the vehicle, negatively.

Driven by popular culture, installing new wheels and tires has become a huge business in North America.

 

[ferretx9]

100 % spot on Z.

As for the tire size and finding replacements -

With little demand for that size ( at the moment ) , it will be a
year or two before more companies start to make that size .

By then all the original owners will need replacements and a
few more vehicles ( may ) / will start to have it as a " stock size " .

At the moment is isn't profitable for tire manufacturers to
set up a factory line to run a size that only a few need , which ( btw )
for the current manufacturer translates into
" we da ONLY ones with it , and you NEED it , $KA-ching$ ! " .