I am planning on new rubber to replace these sh!tty 16" 205/60/16 OEMs. I plan to keep the stock 16" rims for now because I actualy like the way they look. I've already decided on Michelin Pilot Sport A/S tires--a bit costly, but worth it for the handling. And I've read that 225/55/16 is the "ideal" replacement for our TLs, and that is what I will probably buy.

My question: Why is this the best size? Is it better to upgrade to 17", lower profile tires? Will doing that impair the ride significantly? How exactly do I determine the ideal tire size for my stock TL rims? Can anyone who knows about tires give an intelligent answer to these questions?

Thanks in advance for your answers, just trying to understand the standard recommendation!

 

In answer to your questions.....
"Why is this the best size?" Couple factors in determining what size would be ideal. Factor in rim width and the rolling diameter that will closely matches stock specs. 225/55-16 closely matches the stock rolling diameter of 25.69" and it will safely mount onto a 6.5" wheel.
"Upgrade to 17" - impair ride?" It's all about personal preference. Upgrading to a larger diameter wheel will give you a more agressive, sportier look. Also will provide increased handling due to the "shorter" sidewall. Also, with that "shorter" sidewall comes a stiffer ride, not much cushion to absorb those bumps in the road.
"How exactly do I determine the ideal tire size for my stock TL rims?" Go Here. Very useful tool.

Hope this clears up the water a bit.

 

Thanks, Lawaia! That pretty much clears things up. The tire size calculation page is excellent, though the owner's excitement over the Buick Regal does not compute with me. To each his own I guess.

Is it safe to assume that ride quality will not suffer with 255/55/16 tires, since the rolling diameter of the tire is effectively the same as stock?

The only thing missing from the size calc page is the effect of mounting a larger-sized tire on the same sized-wheel (e.g. placing a 17" tire on a 16" wheel, as I was asking). Have people tried this on their TL-P? How harsh is the resulting ride? This I'm just asking out of curiousity.

 

You're welcome. I'm going to assume you meant 225/55-16, not 255 right? You will not sacrafice ride quality as the same amount of sidewall will be present.

It is impossible to mount a 17" tire on a 16" wheel.

I personally upgraded to CL-S wheels and am rolling on 215/50-17. Ride quality remained the same, however handling and performance was greatly increased with the Toyo Proxes T1-S.

 

Even I can figure out that major rubbing would occur with 255/55/16 tires if they can even be installed! What a typo.

I'll be buying the tires once I get back from my 2600 mile road trip in a couple of weeks--I'd rather wear down the OEMs than than the new tires. Will post a review when they're mounted.

Thanks again!

 

Good info on tire calculator. Thanks