Mismatched front and rear tires BAD idea?

Do not mismatch tires, or manufacture or tread design period! Tires must match!

 

retired 4999: While your comment MAY be the "standard and acceptable" response - I disagree with the "tires MUST match".
I had run snow tires on the front of my 2005 Prius for 2 Winters (front only - all season radials on the rear). When we sold the 2005 and bought a 2010, I kept the front wheels/tires from the 2005. I am now running the front snow tires on the 2010 this Winter w/o ANY problems at all. The only "issue" is the low tire symbol is lit on the dash for an obvious reason. There have been/are no problems with handling issues - we have had ice, deep snow, etc. this Winter and the car and its tires are performing just fine.

 

Must Match?
Or
Bad Idea.

Debate all you want...but I'm going to say bad idea....perhaps very bad idea.

Even if the difference doesn't create a perceptible handling difference feel, I can't believe running mismatched tires isn't a reduction in performance.

And IMO tires are so important to vehicle operation and safety, that I'm going to say...bad idea.

 

Ok! I give a little.
A Bad Idea!
I believe that putting snows on front and regular tread on the back is just asking for the rear end of the car to end up in the front!

 

For budget financial reasons once, I needed a set of 4 tires but could only afford to buy two at a time, and it was necessary to buy the two just to stay on the road...one of the tires had gone dangerously bad.

So I drove a set of mismatched tires for about 6 weeks while I saved up to buy the second set of two.

I can't say I really felt a huge difference.

But I believe the vehicle was safer once I got 4 matching tires all near the same wear point with the same tread design.

I also bought a used car once that had mismatched tires on it. Again, I honestly can't say it felt dangerous, but once I got a set of matching 4 my gas mileage significantly improved.

I don't think a mismatch will necessarily immediately send you into a ditch, I believe it's doable. But is it recommendable? No...I have to say avoid it if possible.

 

The handling issues that this can cause are not something you will experience very often, or for most people, even be able to attribute to the tires after having an incident. Nonetheless, it is well known, and I can speak from personal experience that the snap oversteer that can occur is incredibly dangerous and impossible to control. Hit the right combination of surfaces and you may find yourself suddenly facing the wrong way at a high rate of speed. It's honestly one of the most dangerous things you can do to your vehicle. Spend the couple hundred extra bucks and get matched tires!!!

 

Apart from the safety angle. One other problem you are likely to come across with different size tyres front and rear is that at speed the ABS VSC warning light is likely to come on as the front and rear wheels rotate at different speeds because of there different radius. The computers thinking the car is in a slide.

John (Britprius)

 

185/65/15 will be fine on a Gen III and narrowing the tires for winter use is actually not a bad idea. Your speedometer will be off by 2% meaning when it reads 60 you'll be doing 58.8, but no big deal (although if your Gen III is anything like mine which already indicated 2mph high you'll now be at 3+, but anyways).

If you need to replace two of the snow tires, buy the 185 size. I do question the value of used tires if two of them already need replacing. I'd think you could do better than that on the used market.