Hi
I have a 2011 Tahoe with stock Brushed Chrome rims 20" wheels. I use it mostly highway driving, no off road!
I want to know what the next size larger than 275/55R20 would be and if will effect speedometer or electronic monitoring of engine emissions or Safety?

Thanks in Advance
Sal

 

Welcome to the Forum Sal.

There are two ways to have a larger tire... Wider, Taller (or both).
There will be effects in changing/increasing either.
The next size in Wider is 285, which also will produce slightly more height.
The next size in Taller is 60R.

For optimum performance...
The width of the Tire, and the width of the Rim, should be the same.
This allows the Sidewalls to operate straight up and down, giving you less sway and with adequate pressure, the best protection from Road Hazards.

When you put a wider Tire on a narrower rim...
You create an "oval", which causes unintentional movement from side to side reducing the "crispness" of control.

When you put a taller Tire on your existing rim...
The Speedometer will read slower than your actual speed.
You will experience (a little to a lot) of perceived reduced braking power, and overall power reduction of your vehicle.
There may be a change in your Gas Mileage (usually negatively).
You also increase the height of your vehicle (raising center of gravity).

Many put larger Tires on their rides, and, if you are willing and aware of the differences it makes, then ok, but may I ask...

Why do you want larger tires ?

For your reference...
The OEM width of your Tire/Rim assembly should be 8.5".
The OEM height of your Tires should be 31.9".
(these numbers are what GM thinks works best on your ride)

 

Thank you for a quick response and the competent level of detail which is exactly what I was inquiring about.
To answer your question, I felt the tire looked a little small for size of the fender well. But realized after I wrote this original message the taller tire may rub the front to back bottom edge of the fender. Plus all the negative effects you mention, I will go with the original size.
FYI I'm strongly considering Michelin LTX M/S2 and found Costco has a great price.
Regards,
Sal

 

Sal,

That's a very good choice !
Smooth ride, AND, they have a very good capability for wet and Ice.

Here's something you may not know...
When you get a new set of tires, they need a break in period.
This is because they haven't been totally "cured" when the left the Factory.
Note (stamped on the sidewall) on those tires, a MCIP (Maximum Cold Inflation Pressure), which is well above the normal 30psi that is mentioned on the door.
You should inflate the tires within 10% of that higher pressure, and run the tires about 400 or so miles to break them in properly.

Beyond that, the continued use of that higher pressure, will permit your tires to perform their best. With higher pressure you'll get better Gas Mileage, enhanced control and better ability to bear the weight of your (quite heavy) vehicle.

If you have any other questions, please visit us again.
Good Luck and stay safe.