Can I use tires of different diameters

tires
winter

#1

Winter tires are now mandatory in Quebec. I had bought winter tires for my previous Montana and changed to an uplander.

I had winter tires for the Montana, 215P70R15 which is 2 years old. The uplander tires are 215P70R16. Are there any safety issue in using my 215P70R15 winter tires?

Thanks in advance


#2

We are talking all four tires, not just two, right? Running two 15s and two 16s would probably make the ABS go crazy.

Assuming that your 15" rims fit the bolt pattern, and you don’t mind how it will look, and you can adjust to the speedometer being way off, it should be OK.


#3

Yes, all four tires will be 15".
Thanks a lot Manolito. I’ll just purchase 15" rims that would fit the bolt pattern.
Considering winter is only 4 months and I don’t really drive fast during winter, it’s good to know that the speedometer and odometers will only be the issue.


#4

You should be good to go. Speedo and Odometer will read about 3.5% fast


#5

I’ve heard of cases where using different diameters tire has caused the ABS system to malfunction. I don’t have specifics, so you should check to see if your vehicle is one of those!

But losing ground clearance in an area of heavy snow fall (Quebec) doesn’t sound like a good idea. May be the smart move is to sell the 15" and get a complete new set of 16".


#6

No ABS problem if all four tyres are replaced. Ground clearance difference will be something like ? inch or less.


#7

Make sure that the 15" rims fit over the brake calipers! They might not even if the bolt patterns are the same.


#8

Excellent point! I forgot about the brake calipers.


#9

And the offset.


#10

I’m not sure about your Montana, but all wheel systems transfer cases can be destroyed by using different size tires. I tried to purchase one new tire when one was shredded on my Subaru, tire dealer wouldn’t sell just one or two. I went home and googled tires and transfer case and was amazed at all the vehicles and warnings. Even using the replacement spare for too long puts one at risk for a very expensive repair. Who knew?


#11

Yes, using a set of mismatched tires can damage a AWD or 4WD systems. It is also not a good idea to mix tires even if they are the same diameter. In this case, the OP wants to use a set of matched tires but on a different and smaller diameter rim. Hopefully he can find a rim that will work. Clearences and offset will need to be checked.