OK to mix these tires?

[Mermaidman]

I have a FWD car. Will there be problems if I install
Pirelli z-rated tires on one axle
Michelin h-rated low-rolling resistance tires on the other axle?

Tires will be the same size, and are "all-season." They're for my daily commuter.

edit: "Why?" Because I'm cheap. Two of my existing tires are still good, and I found a good deal to replace the two that need replacement.

 

[michal1980]

why?

 

[JulesMaximus]

Put the newest tires on the rear axle and you should be fine. Replace the front tires before the next rotation.

 

[satyajitmenon]

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=52

When tires are replaced in pairs in situations like these, the new tires should always be installed on the rear axle and the partially worn tires moved to the front. New tires on the rear axle help the driver more easily maintain control on wet roads since deeper treaded tires are better at resisting hydroplaning.

If the front tires have significantly less tread depth than the rear tires, the front tires will begin to hydroplane and lose traction on wet roads before the rear tires. While this will cause the vehicle to understeer (the vehicle wants to continue driving straight ahead), understeer is relatively easy to control because releasing the gas pedal will slow the vehicle and help the driver maintain control.

However, if the front tires have significantly more tread depth than the rear tires, the rear tires will begin to hydroplane and lose traction on wet roads before the fronts. This will cause the vehicle to oversteer (the vehicle will want to spin). Oversteer is far more difficult to control and in addition to the initial distress felt when the rear of the car starts sliding, quickly releasing the gas pedal in an attempt to slow down may actually make it more difficult for the driver to regain control, possibly causing a complete spinout.

 

[ThatsABigOne]

Oversteer is a lot more fun.

 

[Zenmervolt]

Oversteer is a lot more fun.

Right up until you're spinning through the oncoming traffic lane. 😛

ZV

 

[ThatsABigOne]

Right up until you're spinning through the oncoming traffic lane. 😛

ZV

Whoops! 😀

 

[exar333]

Right up until you're spinning through the oncoming traffic lane. 😛

ZV

This.

Throw the new tires on the rear and you are good to go.

 

[Ferzerp]

If the front tires have significantly less tread depth than the rear tires, the front tires will begin to hydroplane and lose traction on wet roads before the rear tires. While this will cause the vehicle to understeer (the vehicle wants to continue driving straight ahead), understeer is relatively boring because releasing the gas pedal will slow the vehicle and help the driver maintain control.

However, if the front tires have significantly more tread depth than the rear tires, the rear tires will begin to hydroplane and lose traction on wet roads before the fronts. This will cause the vehicle to oversteer (the vehicle will want to spin). Oversteer is far more FUN to control and in addition to the initial exhilaration felt when the rear of the car starts sliding, quickly releasing the gas pedal in an attempt to slow down may actually make it more difficult for the driver to regain control, possibly causing a complete spinout.

fixed 😉

 

[_Rick_]

Remember kids, you can catch a drift, but if you're understeering, you'll only ever keep going straight 😀

Anyway, with FWD I'd put the new tires up front. And I'd drive like I was on shitty tires all day long.
Also, with FWD and front-grip you can power out of oversteer, like this:
https://www.youtube.com/watch?v=gZzmfXfBckM

 

[Don Vito Corleone]

Those seem like a rather strange combination to me, but I suppose as long as you're not driving in snow you should be OK.

 

[Ferzerp]

Those seem like a rather strange combination to me, but I suppose as long as you're not driving in snow you should be OK.

Well, I'm confused on why he has uneven wear and has 2 good tires anyway. He specifies that it isn't a staggered set up.


Also, ignore the guy telling you to put the good tires on the front. Normal people (and frankly anyone on public streets) should not intentionally increase oversteer.

 

[Zenmervolt]

Remember kids, you can catch a drift, but if you're understeering, you'll only ever keep going straight 😀

Not at all true. Not even remotely close to true.

The instinctive response of non-race-drivers to any emergency situation is to release the accelerator rapidly.

When the car is oversteering, this instinctive response makes the oversteer worse because it transfers weight to the front (increasing front grip) and makes the rear even lighter (which further reduces rear grip).

When the car is understeering, the instinctive response reduces the understeer and significantly increases the chances of the driver avoiding a massive accident.

It takes much more skill to catch and correct oversteer than understeer.

Anyway, with FWD I'd put the new tires up front. And I'd drive like I was on shitty tires all day long.

This is an incredibly stupid recommendation.

ZV

 

[_Rick_]

Not at all true. Not even remotely close to true.

The instinctive response of non-race-drivers to any emergency situation is to release the accelerator rapidly.

When the car is oversteering, this instinctive response makes the oversteer worse because it transfers weight to the front (increasing front grip) and makes the rear even lighter (which further reduces rear grip).

When the car is understeering, the instinctive response reduces the understeer and significantly increases the chances of the driver avoiding a massive accident.

It takes much more skill to catch and correct oversteer than understeer.



This is an incredibly stupid recommendation.

ZV

Well, I was bullshitting slightly, but even so, the other day my car understeered on me (I carried a bit too much speed into a roundabout, didn't get any turn-in, even under brakes) and this feeling of total helplessness as you just plow on straight is horrible.
At least with oversteer I still have some marginal control over the car, and I can control the slip angle - even if the choice is only in the angle I go into the ditch.
Of course, with power understeer I can somewhat do the same, and admittedly, getting lift-off oversteer (I may also have touched the brakes 😳) from over-correcting power-understeer is also pretty poop-inducing, but more so because you suddenly get the feeling that you're completely out of grip now, as the front wasn't going where you wanted it to only moments ago. (Don't do mid-corner adjustments if you can help it, kids!)

I'd rather have a car with a "pointy" setup rather that one that will turn me into a complete passenger if I hit some standing water.

Also, if you have less grip front, and you brake, what happens is that you lock up the fronts, and then you just get catastrophic understeer. Sure, with modern ABS you should get some modicum of control, but less than if you had proper grip on the front.
Plus, the front tire is also the one that has to take greater loads under both braking AND acceleration - so wear will be greater at the front.
If OP wants to quickly get another pair of tires. he might as well put the skinny ones up front. But if he wants the current odd set to last as long as possible, putting the skinny ones to the rear should give him more miles out of the worn out ones.

On the other hand, if you have no idea how your car is balanced, then just get 4 identical tires, instead of upsetting the balance by mixing tires. At least by sticking the stickier ones to the rear, you won't lock-up the rears under braking as easily.

 

[JulesMaximus]

Well, I was bullshitting slightly, but even so, the other day my car understeered on me (I carried a bit too much speed into a roundabout, didn't get any turn-in, even under brakes) and this feeling of total helplessness as you just plow on straight is horrible.
At least with oversteer I still have some marginal control over the car, and I can control the slip angle - even if the choice is only in the angle I go into the ditch.
Of course, with power understeer I can somewhat do the same, and admittedly, getting lift-off oversteer (I may also have touched the brakes 😳) from over-correcting power-understeer is also pretty poop-inducing, but more so because you suddenly get the feeling that you're completely out of grip now, as the front wasn't going where you wanted it to only moments ago. (Don't do mid-corner adjustments if you can help it, kids!)

I'd rather have a car with a "pointy" setup rather that one that will turn me into a complete passenger if I hit some standing water.

Also, if you have less grip front, and you brake, what happens is that you lock up the fronts, and then you just get catastrophic understeer. Sure, with modern ABS you should get some modicum of control, but less than if you had proper grip on the front.
Plus, the front tire is also the one that has to take greater loads under both braking AND acceleration - so wear will be greater at the front.
If OP wants to quickly get another pair of tires. he might as well put the skinny ones up front. But if he wants the current odd set to last as long as possible, putting the skinny ones to the rear should give him more miles out of the worn out ones.

On the other hand, if you have no idea how your car is balanced, then just get 4 identical tires, instead of upsetting the balance by mixing tires. At least by sticking the stickier ones to the rear, you won't lock-up the rears under braking as easily.

You know, there is an entirely different solution to this problem... one that I'm sure you haven't thought about. One that would have easily solved every single problem you had in that roundabout and wouldn't cost you a thing and in fact would have made you and everyone around you much safer.

SLOW THE F DOWN and STOP DRIVING LIKE AN ASSHOLE ON PUBLIC ROADS!!!

 

[Zenmervolt]

Well, I was bullshitting slightly, but even so, the other day my car understeered on me (I carried a bit too much speed into a roundabout, didn't get any turn-in, even under brakes) and this feeling of total helplessness as you just plow on straight is horrible.

That feeling is a whole hell of a lot less horrible than the one you get when your car is spinning.

Also, to get that level of understeer you aren't carrying "a bit too much speed." To get that level of catastrophic understeer you have to be driving like a complete maniac.

I'd rather have a car with a "pointy" setup rather that one that will turn me into a complete passenger if I hit some standing water.

On a track, I'd agree with you. There's a reason my track-focused 944 is set up to be much livelier than my daily-driver Volvo.

We're not talking about track driving though. We're talking about a FWD commuter car.

Also, if you have less grip front, and you brake, what happens is that you lock up the fronts, and then you just get catastrophic understeer. Sure, with modern ABS you should get some modicum of control, but less than if you had proper grip on the front.

Under braking, you get a lot of weight transfer to the front which vastly increases front-end grip. Unless the front tires are absolutely completely worn out, you'll still lose traction with the rears first, even if the rear tires are new.

And, in any case, when the rear end loses grip under braking, the car is massively at risk for spinning. That's why when ABS was first coming out many vehicles had rear-only ABS. If the fronts locked, you simply kept going straight, but if the rears locked, you'd fishtail, which is much more dangerous.

Plus, the front tire is also the one that has to take greater loads under both braking AND acceleration - so wear will be greater at the front.
If OP wants to quickly get another pair of tires. he might as well put the skinny ones up front. But if he wants the current odd set to last as long as possible, putting the skinny ones to the rear should give him more miles out of the worn out ones.

Yes, because saving a few bucks by getting an extra couple thousand miles out of a pair of tires is totally worth a significant safety risk. 🙄

When replacing tires 2 at a time, the new tires always go on the rear axle. Period, end of discussion.

ZV