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Tire Size Question

Hello out there…I’m a new member and would like to ask a question…

I bought a 2011 Toyota Sienna for my wife which she loves. We live in upstate NY which has plenty of snow, not counting this past winter. My friend gave me a set of snow tires mounted on rims already that look like the bolt patterns fit, but the tire size is a little small. Would there be any issues, other than the speedometer and odometer being off by a little if I use them?

OEM tire is 235/60/17 T rated 100 load index

Winter tire is 225/55/17 V rated 101 load index (nice Michelin PA3 Alpins with 8-9/32nds tread)

I know that my speedometer will run faster than I am really going and that my odometer will read a little higher than real, but am just worried about safety issues mainly will using a smaller overall diameter tire.

Thanks.

I would not do it. I have a 2011 Sienna also and I often have six people in the car with our musical instruments. I think I am running at the load limit and would not want to have a tire that has a lower load capacity. Toyota issued a recall on my Sienna which consisted of a new decal to affix to the left pillar which actually lowered the weight limit.
Tire size is more critical on modern cars than it was on cars of the 1950s and 1960s. However, back then we might go up a tire size, but never down. I ran 7.35 x 14 in place of 6.95 x 14 on my 1965 Rambler Classic. I think you should stay with the size recommended by Toyota.

I agree with Tridag. You may be able to go with 225-65/17 so that the outside diameter remains constant, but I would never down size from the OEM size. This may affect your load rating as well as other safety isdues. You have a 2011 Sienna that has a particular size tire with traction and stability control as well as abs , all computer controlled based upon the input from the sensors in the abs dependent upon tire rpm. That will change…You have more then just speedo error to worry about.

I disagree only because the winter tire has a higher load rating (101 vs 100), and only if all four tires are the same. You cannot mix two summer tires with two winter tires that are different sizes. It will affect your speedometer but it should not affect your abs or traction control.

Even with the Load Index being close to the same, this doesn’t sound like a good substitution. Diameter is way different - nearly 5%.

To me, the rim is more likely to be a problem. The bolt pattern may match, but it also needs to match the hub. If the hum hole on the rim is too small, it wont mount, if too large, it wont center. Also the off set should be at least close or it will put a strain on the wheel bearings. I still think the tires will be ok though.

Found this online the other day, it will put into perspective the differance in size… Capri is right its almost 5% different, with the radius being off .7 inches…

http://www.miata.net/garage/tirecalc.html

IMHO a Sienna is not a vehicle that will tolerate tires of mismatched size, front & rear, well at all. In the event of an evasive maneuver the difference could easily mean the difference between avoiding a crash and being in one…possibly even a rollover. It isn;t worth taking this risk with your wife and children just to save a few hundred lousy dollars.

And then there’s the rim problem to consider.

I think it’s a mistake, with potentially serious consequences. When you’re looking at parts critical to safety, always think “how would it matter in the worst-case scenerio”.

Thanks for all of your input.

Of course it is all 4 winter tires, I wouldn’t consider it otherwise. The rim matches up exactly, they winter rims are OEM Lexus LS rims with same offset, diameter, bolt pattern and hub circumference.

Basically, the snow tires are just smaller than the oem sienna tire size. I’ll probably keep the rims and buy new snow tires.

Thanks again.