Question about tire repair

[dill chips]

And who "verifies" it as structural or superficial? There's not a responsible tire shop that's going to say it's ok. Been there, done that.

Tire shops could verify that a tire needs replacement to make money, not because it actually needs to be replaced.

While I doubt hairline cracking on the sidewall goes any deeper, I ultimately agree that there isn't really any way to verify for sure, and that you're best off replacing the tire(s) anyways..

It's also important to keep in mind that poor/no tire pressure monitoring and adjustment habits by the driver(s) of the vehicle can easily account for a higher risk of tire failure or blowouts, especially with the way some ppl drive (@BoomerZoomr said it),

 

[BoomerZoomr]

Since we are talking about this subject… isn’t this a hoot?

Mazda expects us to play musical wheels on the side of the road.

 

[dill chips]

Since we are talking about this subject… isn’t this a hoot?
Mazda expects us to play musical wheels on the side of the road.View attachment 383245

They don't expect you. They suggest that you do. There is a difference.

While the recommendation is sound, in the event of a front flat, Id rather just put it on the front if I'm on the side of a busy road with hand tools.

 

[N7turbo]

Well you aren't supposed to use the spare on a drive wheel, despite many not knowing that. Also, it won't even fit on the turbo front brakes, so you must use it on the rear. There is no other way.

 

[BoomerZoomr]

Well you aren't supposed to use the spare on a drive wheel, despite many not knowing that. Also, it won't even fit on the turbo front brakes, so you must use it on the rear. There is no other way.

I was more concerned with how the smaller diameter spare on the front might affect the inner workings of the front transaxle, rather than vehicle handling. But if the dang spare won’t even fit on the front, the point is moot. Mazda dances around that tidbit of information in the owners manual. Thanks for the info.
If I remember correctly… when airing up my spare today, I noticed the spare uses a 17" wheel. The other four are 19"

 

[madar]

So we are all on the same page here: Nutball drivers should absolutely keep their tires in top shape for the safety of all.

No, nutball drivers should stay the hell off the road....

 

[N7turbo]

Tire pressure is based on load. My Miata only calls for 29 psi due to the lesser weight on the tires.

 

[dill chips]

After 500+ miles, the mpg is now around 35. I checked the tire pressure today and all 4 were around 34. I suppose the shop's tire inflator (running from an air compressor) would read differently from my cordless handheld unit. However, the door jamb sticker says 36/33. I thought it makes sense for the CX-3, not because she's got a Skyactiv 3.0 in the front, but that her rear end is short and light.

What's the reason for having all four the same? I have heard before that 35 all around is a safe bet on most cars.

I replaced the intake air filter too.

Most likely the difference is due to some variation in ambient temperature inside the shop vs outside, which caused the change in temps.

I showed you the global owners manual for your cx-3 in our discussion over on the belt tensioner thread - Mazda actually recommends a 33psi square setup for your specific AWD model when driving with a light load - 34 square is an excellent starting point.

You can safely ignore the suggestion to add more tire to the rear axle. Mazda does this in North America only because apparently North American drivers don't check their tire pressures when adding weight to their vehicle