Mismatched car tyres - what would you do?

I think the matching thing is just sales-speak. I always thought and followed it though. A few random punctures and issues getting same brand tyres we’ve run mis-match for a year or more. No issues and can’t notice any difference when driving.

If FWD id also suspect mismatch rear not an issue.

I’m neither mechanic nor petrolhesd tho.

Replace just the Triangle with another Pilot Sport.
I wouldn't worry about having two tyres of the same type at different wear levels.

Assuming UK based. I'd do what I did when my last car arrived with similar mismatch (also a nexen/Michelin mash up) and perishing tires oh and a day 4 of ownership date with a 6inch nail into the sidewall.

Fitted 4 all seasons more suited to the year round climate we live in.

Not looked back.

How ever as below- if I didn't have the money I also wouldn't lose sweat over a mismatch so long as they were not perishing or damaged. - a misspent youth rolling on 20 quid ditchfinder specials and junkyard rescues taught me that the exit point is beyond the speed at which I'm willing to drive on a public road

Replace just the Triangle with another Pilot Sport.
I wouldn’t worry about having two tyres of the same type at different wear levels.

If you don't have the money, it does not matter.
If you have the money, +1 this ^
Then put the Triangle on your spare wheel because that'll be x years old by now.

Fitted 4 all seasons more suited to the year round climate we live in.

If you really really have the money. This !

+1 on pop another Pilot sport on.

Having experienced the difference between a good and a crap tyre, I think you might notice depending on what right corner you were going around.

johnners

Replace just the Triangle with another Pilot Sport.
I wouldn’t worry about having two tyres of the same type at different wear levels.

+1 - especially if it's FWD - the rears are just along for the ride and will outlast the fronts at least 2:1

Personally, would just swap the back two (for a premium brand) and keep the Michelin for the spare.
Edit - I might also move the Nexens to the back, to have two fresh tyres on the front.

I'd leave it, personally. It's not like one's cross-ply.

It’s not like one’s cross-ply.

This. The rears just get dragged around and don't really do much.

Plus you can't see both sides of the car at once so no-one can tell you e got 3 different brands on 😉

As they've got loads of life left I'd leave them.

I’m sure the official advice is that you’re meant to have the ‘best’ tyres on the rear even on a FWD car.

I would buy a Pilot Sport. Wouldn't bother swapping back to front. Who knows which pair would be grippier in what conditions anyway?

I agree with new tyres to the back when they are the same all round.

At least have a matched pair on each axle.  Best grip ones on the front.  Seems you can do that with one new tyre.

I had a car from work with mismatched tyres.  It handled like a greased pig on stilts and that was a small light car.  It was borderline dangerous

Tyres on motor vehicles are something I am fussy about - what price safety?

Best grip on the back.

In the event of tyres giving way I'd prefer the nose crumple zone over the side impact bars.

You want the best braking possible.  Most braking is done via the fronts therefore best grip tyres on the front?  No?

The theory is oversteer is more likely to have bad consequences than understeer.

What size are they? I’ve 4 Michelins PS’s that are 2000 miles old lying in my garage that I want to sell on

You want the best braking possible. Most braking is done via the fronts therefore best grip tyres on the front? No?

No.

What happens in your scenario is the rear swings round under hard braking

Because I care about how my cars drive I'd be replacing the rears with a matching pair immediately and seeing if I get on with the fronts.

Better tyres to the rear...

What happens when you don't...

(Not in this case) but radials always go to the rear if there are a mix of paired types

@houns, 225/40 18.
I think single Pilot Sport is the answer.

What's on your spare wheel (if you have one) you might get lucky and find a pair and put the miss match on the spare.

Personally, if they are black and have good tread, I'd leave it. We are almost out of the cold ❄️ weather and you don't strike me as a boy racer 🤣

You do know as soon as you replace them, you will run over a massive nail and ruin it! But if you leave them on you will never get a puncture! It's sods law

Does it have a spare and is the same size? Does this help at all? If not I'd check ebay for a part worn Michelin to match the current one.

I genuinely wouldn’t worry about matching tyres.
Unless one or some were ditchfinder specials, they’d be getting ripped off asap.

You want the best braking possible. Most braking is done via the fronts therefore best grip tyres on the front?

No, best on the back. The front has more grip under braking due to weight shift.

Lose the front/understeer during a swerve/corner and the natural reaction is lift off/brake, which transfers weight forward and can recover the siuation.

Lose the rear/oversteer unexpectedly and that natural reaction to lift off makes it worse and you crash.

Best tyres on the back makes the car more prone to safer understeer, especially in the wet.

OP, check the age of the tyres (4 digit code is week and year). If either are really old, change them anyway.

I know nothing about tyres except this public information film from when I was a kid.

Spare is a space saver so no disco in that regard. Well, I say that, it was some foam and a compressed but I’ve just bought a space saver.

@tuboflard

I know nothing about tyres except this public information film from when I was a kid.

Brilliant!

Ditch the triangle one TBH. Never heard of them but they are apparently a big tyre manufacturer from China ! Nexxen are fine, but the OCD in me doesn't like mis-matched tyres on an axel.

what would you do?

Drive it and replace tyres when the wear out

This thread just made me check my tyres! The right front is fine, the left front is goosed so I now have the same dilemma.

Think I’m going to bite the bullet and just buy 2 fronts. Just checked and a set of goodyear asymmetric on my Mazda 6 cost more than I paid for the same tyres on my boxster 2 years ago despite being smaller.. ouch….

When did tyres get so expensive

My preference is always not to have a mismatch but on a "cooking" model front wheel drive car and sensible driving I'd personally not think about it too much on the back until something triggered a change of one then I'd do a pair and probably wouldn't run either down to the minimum.

I ran a mismatch pair of a part worn to get me home when I got a flat 150miles from home on a Sunday lunchtime and whatever was there before. Did a few thousand on those before a screw put an end to the part worn and then did the pair. Done the same after a puncture on a previous car.

I drive smooth, plan ahead and am rarely on any pedal hard never noticed any difference or issue as I'm always well within tyre limits. If I drove a high performance car I'd possibly feel differently as the loads are larger.

Depends a lot on the car, too, you can have issues with some stability controls and clever ABSs where all 4 corners get dragged down to the performance of the worst. Nexen make good stuff ime, depends on the exact model. Pilotsports are fab, though this time of year not at their best and they absolutely suck at snow and ice. Triangle are ime MOT replacement shit... But in all likelihood it's fine as it is. 3 good tyres is better than most people have I reckon. I'd definitely go out and do some testing, personally.

If you don't have some sort of diff complications requiring matched wear on both sides, I'd bin the triangle and get a new pilotsport, since you say the old one's got lots of life left. Depends what "lots of life" means to you I guess

And theeeeen, the STW argument...

...I'd put the most grip on whichever end your particlar car works best with the most grip on, and find that out by experimentation. The "most grip on the rear" rule of thumb is fine as far as it goes, it's the only guidance you can give that's going to work out OK in all circumstances and never be terrible. If you want a simple, reliable answer then do that, it's good advice. If you want the absolute best performance out of your car, maybe do that, maybe don't.

As said above in most cars the front does most of the work, so having a suitable amount of front and rear grip will give the best results. That's not automatically "best on the back" or "best on the front" or "best to be the same all round", because of weight distribution, brake strength and bias, driver aids, how well set up the car is, allsorts.

Simply, the choice isn't "understeer or oversteer", it's "understeer or oversteer or maybe just carry on without any fuss." Unless your entire approach to driving is "wait til the front slides then slow down" rather than "drive in control" of course. But reducing it to "a choice of this loss of control or that one" is just wrong.

More grip on the front doesn't reduce the grip on the rear. It just increases the possibility that you'll use that front grip to get into a situation where the rear breaks loose. But that point will mostly be a lot higher up, ie, you've got a window between "I have run out of front grip" and "I have more front grip so now I have run out of rear grip" and in that window, you've got more grip full stop- more brakes, more control.

How big that window is, is what really counts, because the real world situations include "ran out of front grip and the rears were fine, so I hit a baby robin" vs "Had more front grip and the rear was still fine so I evaded the bus full of nuns" and yes "ran out of rear grip and lost control even though the fronts were fine so I hit Surfmatt".

(obviously this also gets exaggerated and easier to read with big disparities- something like a pilotsport on the front and a decent touring tyre on the back in the dry is still "both ends have excellent grip") and so the window is pretty big. Something like pilotsports on one end and absolute crap on the other is massively more likely to go "one end has not enough grip", not because it has less than the other but because it's outright bad and the other's outright good, the window's small)

The question is, with your car, your tyres, your nut behind the steering wheel etc, which actually happens? Like, my first car's rear end really didn't do much except follow. The brakes were piss-weak and the weight distribution meant that even though for a while it had adequate tyres on the back and good ones on the front, it was a total nonissue. You could just about provoke a "front is gripping but rear isn't" scenario, with enough effort but in real world driving it just wasn't happening. But swapping them around would have made it less safe. Obviously improving both ends would be best.

My current car does a lot more with the rear, if I'd had such a big disparity it'd be bad news. But it still functions well with great grip on the front and a little bit less on the back, it's just less extreme. It just requires both ends to be decent in order to work, good/bad would be bad and bad/good would be bad. But while good/better is good, better/good is better.

And all of that, is why the rule of thumb is really a good idea, you need to think about and try a whole lot of things to get past it safely.

@northwind I'm glad someone else typed all that out. Thought went through my head but just couldn't be bothered.

the car is a fairly boring 1.6l estate and I’m not hugely into making progress…

Realistically, for the 50 weeks of the year when it isn't snowing, does it matter so long as they've got tread?

Sure, if the OP was driving like they'd stolen it then I'd absolutely want four consistent and reliable corners. But Driving Miss Daisy in a 1.6 estate, your money would be better spent on throwing a bag of cement in the boot and revisiting the question come November.

IMHO. Please don't die in a car crash.

Lose the front/understeer during a swerve/corner and the natural reaction is lift off/brake, which transfers weight forward and can recover the siuation.

Lose the rear/oversteer unexpectedly and that natural reaction to lift off makes it worse and you crash.

I can't imagine how you have to drive to have this problem. It's only ever happened to me once, flooring it off a sliproad in a car with high torque. Don't you people read the road ahead or something?

Car braking performance is important of course, because it happens unexpectedly. But front/rear balance in a slide? Really?

Lose the front/understeer during a swerve/corner and the natural reaction is lift off/brake, which transfers weight forward and can recover the siuation.

Lose the rear/oversteer unexpectedly and that natural reaction to lift off makes it worse and you crash.

I don't think this is the case with modern ESP. And by modern I mean from the last 15-20 years.

Tyres are your only connection to the road. There is a massive difference between good v's bad tyres in different driving conditions. The only thing stopping you and your family (or someone else's family) from becoming another statistic. Always amazed by those people who skimp on car tyres to be honest. The fact that your car came with mostly unmatched tyres or budget tyres in the first place would worry me IMO. Makes you wonder what else has been neglected about it.

I'm really surprised so many of you would drive on bad tyres. I'd bet most of you wouldn't be willing to ride on bad tyres.

Me, I'd look for a set of wheels and tyres for the car on ebay and swap the lot.

I'd never have mismatched tyres on an axle and won't have anything but premium tyres on my cars.

Road conditions are too variable and too crowded to be worth saving £100 at the expense of a potential accident.

The fact that your car came with mostly unmatched tyres or budget tyres in the first place would worry me IMO. Makes you wonder what else has been neglected about it.

I did wonder if it’s would come up.
The car comes with Pilot Sports as OEM, the front have worn out at 25k so we’re replaced with the Nexxen (not what I’d choose but I have found these are what a lot of dealers put on), they’re generally OK tyres.
The Triangle on the back was a cheap puncture replacement as they knew they were selling the car. The price I paid reflected this.

I’m really surprised so many of you would drive on bad tyres. I’d bet most of you wouldn’t be willing to ride on bad tyres

I don't think that they're necessarily "bad" tyres although there is a difference between the Michelin (A) and Triangle TH201 (C) in the EU wet grip capacity labelling for the size given ^^.
Both are XL-rated with a 92-Y load-speed rating, so make sure that this agrees at each corner with the vehicle tyre ratings (sticker/handbook)

I tend to put new on the back, then move them to the front when the fronts need replaced.
That way I always have good, reasonably new tyres on the back & don't end up binning them due to age/perishing as they basically don't wear on the back.

This also plays well with the if you loose the back on a fwd it's harder to catch school of thought, which my limited club Motorsport experience suggests makes for a safer, more relaxed drive.

I would check what else is mismatched, particularly the wear on pads, a visual inspection through the spokes might suffice.

ESP won't create friction that is not there in the first place. It will vector some of it up to a point but it relies on enough being there on the axle that hasn't lost friction.

For stability yes the rear is more important, particularly in the wet but going very low at the front is still a bad idea anyway, so the logic has limits. It wouldn't worry me too much running 4mm at the rear even if I have 6mm at the front. I'll just be aware that a big lift in the rain with a lot of chassis tension might not be a great move, but at mere road speed?

You'll be surprised how much second hand tyres sell for on eBay so maybe an option to mitigate the cost of 4 premium new tyres (with the discounts that this also sometimes generates) with the proceed of the sale of the used ones.

Also, there are all sorts of Pilot Sports. A PS3 from 2005 might not be a particularly useful choice.

thanks for that Northwind. That was my thoughts but I didn't feel able to explain it so well

Unless its a sporty car being driven on the ragged edge:

are they black?
are they round?

Don’t you people read the road ahead or something?

About 75% of the population don't read the road ahead of them. At a guess, about half of them don't even know what language it's written in.

Road conditions are too variable and too crowded to be worth saving £100 at the expense of a potential accident.

Difference between premium rubber and OK rubber on my car is about 5-600 quid, and another 200 or so down to ditch finders.

I don’t think this is the case with modern ESP. And by modern I mean from the last 15-20 years.

Yeah, it'll likely be fine on tarmac, wet or dry, get a little bit of gravel and/or standing water/ice and instead of having a nice smooth curve of grip behaviour, you have a step change. Even a bad camber can be enough when combined with other factors.

Drive it and replace tyres when the wear out

Me too, it's not like they're on anything important like a bicycle, eh?

i wouldn't care less, assuming the size is correct, and load ratings etc

a single crap tyre on the back is going to have very little effect on a FWD car's performance..
High powered rwd car that likes to spin the rear up.. then maybe..

Nexens are a go to brand for me for a not chinese plastic tyre

OP's question - replacing the crap one would be on the 'to-do' list for 'soon-ish'. If you like the 'good' one, make it match.

I'm lucky, I have four knackered tyres... easy (if pricey) decision.

…I’d put the most grip on whichever end your particlar car works best with the most grip on, and find that out by experimentation.

Which is grand if you like to "make progress" and are a great driver, let's just hope the experiment doesn't go wrong when you least expect it to.

The videos posted point out that the car in the test had esp on, it's not perfect it just makes things better and having the best grip tyres on the back is better again.

What would i do - Wife's v70 had Membat passion 'smiling on the road' (designed in italy made in india) tyres on it when we bought it and one trip in the wet was enough to make me drive straight to the tyre place and get crossclimates fitted.
my drive to work ibiza had unknown horrible tyres on it with plenty of tread but i went and got some yokohamas as they didnt have michelins. My Viano had various tyres on it when i bought it, including a brand new Accelera which was available from Camskill for £35 at the time. I got 4 new Michelins straight away and i ebayed the old tyres to a local taxi driver. I just got some smaller OE wheels for the Viano which had some horrible Chinese tyres on it and i didn't even bother asking the wheel refurb place to save the tyres they went in the bin and i got some new Crossclimates.
So i'd fit Crossclimates. If the budget was tight i'd probably stick a pair on the back until i could afford to do the fronts later.

I asked my petrolhead mate.

>>

Nexen are “okay” if it’s not a performance car, but especially if they are new.

I would politely suggest standing water / heavy rainfall / muddy roads can occur all year round.

Drive it and replace tyres when the wear out

i just replaced the tyres on the back of my van because they were starting to perish rather than wear out. they are at least 8 years old, 40k miles and about 3/4 worn...

Drive it and replace tyres when the wear out

Same here.

So many car tyre experts on STW, but it's late March and you can probably survive the next few months at least without that single cheaper tyre catapulting you into a ditch.

Maybe revisit the question in September?

Some of these tyre posts are like some of the suspension posts that come up on here, clearly made by people who do more reading than driving/riding. 🤣
I drive most of the day in cars and vans with budget mismatched tyres and unless you are driving like a dick or too fast for the conditions you'll be fine with tyres that are round and have legal amounts of tread on them.
Some of the previous posters must be racing drivers or something.

there is one thing you cannot argue with and that is in the wet some tyres are significantly better at braking than others. I need to know that my wife's car in particular will stop as well as it possibly can if she has a drama. i don't want to be thinking if only i had spent a couple of hundred more if she had a prang. im no racing driver, in fact people comment that i drive like an old granny, and I'm happy with that. i also get the house alarm tested annually, and i fitted expensive locks on the front door. maybe I'm not normal, but it makes me feel better.

Unless its a sporty car being driven on the ragged edge:

are they black?
are they round?

Could not disagree more.

In fact, of the 2 cars I own, its the distinclty un=sporty one on which its probably even more critical. Becuase thats the car you will be in on a Tuesday evening rush hour, on a wet motorway, when you get the sea of red lights in front of you and all of a sudden that a few quid you saved by fitting 'triangle lassooo sportrider XL's pales into insignificance as you sail into the back to the car in front with your ABS going nuts.

When we purchased my partners car, I fitted 4 new matching Goodyear allseasons.

When I purchased my current 'fun' car I replaced all the unworn but ageing tyres with the correct matching LTS spec tyres.

When I purchased my current daily I purchased 4 matching premium tyres.

When I purchase my next car, which im currently looking for, unless it has 4 decent, matching (at bare minimum across axles but ideally all 4) tyres, I'll be pricing a full set of tyres into the cost.

unless you are driving like a dick or too fast for the conditions you’ll be fine with tyres that are round and have legal amounts of tread on them

It baffles me that on a forum generally populated by people with a level of 'technical' know how, this opinion exists.

"Why bother with that expensive bike, just ride around on something with two wheels and handlebars, anyone could manage an EWS stage on this if your not riding like a dick"

@cougar 's mate is right too.

Its nothing to do with you - I don't care how 'careful' you are as a driver. Its about protecting you from other people, and conditions outside of your control.

Becuase thats the car you will be in on a Tuesday evening rush hour, on a wet motorway, when you get the sea of red lights in front of you and all of a sudden driving too close for the prevailing conditions pales into insignificance as you sail into the back to the car in front with your ABS going nuts. FTFY 😉

Driven lots of cars with mis-matched tyres, quite often making progress. Never found tyres to be an overriding issue, when we replaced tyres getting a match wasn’t a key concern. More important to check pressures regularly imho.

when you get the sea of red lights in front of you and all of a sudden the car in the right hand lane sails into your braking space and immediately hits the brakes driving too close for the prevailing conditionspales into insignificance as you sail into the back to the car in front with your ABS going nuts. FTFY

If we are fixing it for accuracy then I guess we should be considering reality.

Yeah, it’ll likely be fine on tarmac, wet or dry, get a little bit of gravel and/or standing water/ice and instead of having a nice smooth curve of grip behaviour, you have a step change. Even a bad camber can be enough when combined with other factors.

What I meant was that your car probably won't spin if it has ESP. You can still drive too fast and the car will not make the corner, but it won't actually spin. Judging by the accident I saw a few years back you'll just move towards the outside of the corner until you hit something. Bad, yes, but in that situation without ESP the car probably would have spun and rolled due to oversteer or drifted even further out due to understeer, depending on the car. And the tyres it had 🙂

So yes good tyres are very important, largely when braking, but my point was with reference to them being different to each other. I don't think you have to worry much about tyres being different, when you're driving a modern car, but you do need decent ones of course.

ESP can’t do a fat lot if the tyres don’t generate enough grip

I always take the view that the only thing connecting me to the floor are those tyres, so i don't mind spending a bit more on them.
Fingers crossed i won't need to test them, but if something happens i would rather have them than not.

@molgrips

I can’t imagine how you have to drive to have this problem.

Any emergency situation where you need to swerve. Any situation where you get yourself into a bit of trouble such as entering a puddle at speed that turns out to be a bit deeper than you expected. And many people do drive by feel, ie they'll just keep going around that corner faster and faster until they feel the car losing stability.

And as demonstrated by the posters with 8 year old tyres crusty tyres on the back and onto their 3rd front set, it helps even out wear by moving your part worn tyres to the front and using all the tread depth before they are killed by age.

ESP can’t do a fat lot if the tyres don’t generate enough grip

Amen to that and that's what I tried to explain earlier. ESP basically transfers friction from one axle to the other through braking the diametrically opposed wheel. But that's assuming that said wheel has any friction at all. In other words, lose friction on both axles either by losing lateral grip or even longitudinal adhesion (aka traction) and ESP will do absolutely nothing, hence the importance of tyres both in terms of inherent grip but also tread depth in the wet.

And then Michelin throw their tread depth curve-ball...
"The minimum tread depth is 1.6 mm. This means that it is imperative to change your tyres once this limit has been reached to avoid compromising your safety and breaking the law.
But it also means that it is premature to change your tyres before this threshold."
https://www.michelin.co.uk/auto/advice/tyre-basics/tyre-tread-depth

3mm is the oft-quoted minimum for good wet performance, especially under braking, but "The following tyre lines are designed to offer high level of longevity and performance that lasts: ​MICHELIN CrossClimate², MICHELIN Primacy 4+, MICHELIN Pilot Sport 4 , MICHELIN Alpin 6 and MICHELIN Pilot Alpin 5."

^ surprised by that actually. In fairness for me tread depth is also very critical in terms of aquaplaning resistance. I assume that 1.6mm vs 3mm means almost half the volume of water but I don't know what the delta is in terms of mph differential to saturate them between those tread depths.

Michelin is quite specific on tyre models ^^
I get the feeling that it isn't the case that every tyre can run down to 1.6mm and still perform

Golf GTi with mis-matched tyres here. Rarely driven 'on the limit' on the road and did about 80 laps of Castle Combe very nicely last year. Drive to the conditions, expect everyone to be out to kill you and you won't go far wrong.

ESP basically transfers friction from one axle to the other through braking the diametrically opposed wheel.

It does more than that, it will also take over steering.

It's there to prevent a spin or a slide from what I can tell.

It’s there to prevent a spin or a slide from what I can tell.

But in the same way abs is shit with shit tires. It can't work optimally with shit tires.

Of course.

Modern drivers would do well to spend time and training in vehicles without all the aids keeping them on the road.

I dunno, they just need time and training in concentrating and not being dicks.

So Removal of driver aids and spike in the steering wheel.

ESP doesn't typically steer, although it's a collision avoidance feature on some vehicles. It can only steer by applying individual brakes.

The minimum depth is due to the tread patterns. Those listed Michelin tyres are quite an open pattern, so will still clear water reasonably well below the usual 3mm recommendation, however there is still a limit on how well a wide tyre can handle aquaplaning.

It does more than that, it will also take over steering.
It’s there to prevent a spin or a slide from what I can tell.

ESP does not take over steering.
ESP essentially extends functionality of ABS/TC by monitoring the steering position/angle and the vehicle yaw rate to monitor if the vehicle is going in the direction the driver wants it to. If it's not, it'll apply brakes/reduce power/redirect power (only on more advanced drivetrains), to attempt to get the vehicle going in the desired direction.

However if you suddenly spin the steering wheel to the point all wheels are now sliding sideways, it's not going to stop you spinning the steering, and there is not much it can do. It will likely reduce power, but that's of limited help once you're travelling sideways.

ESP does not take over steering.

It does on my car, from experience.

It does more than that, it will also take over steering.
It’s there to prevent a spin or a slide from what I can tell.

It won't take over steering, but it does cut engine power and will apply an individual brake.
It does constantly monitor steering and it'll tell the driver through a variety of cues that it's correcting over/understeer (it doesn't want us thinking that we're better than we are 🙂 )

X-post x2...one of the cues might be a "nudge" of the steering wheel, but that's it

It does on my car, from experience.

It might give the impression it is due to how it's applying brakes/transferring power causing you to need to apply more force to the steering wheel, but it won't take over steering.

It very clearly yanked the wheel and countersteered when I was reckless with the throttle on a motorway slip road. It did what I would have had to do, but far quicker than I could have reacted. Good job, since I wasn't expecting it and I'm not sure I would have done the right thing.