Do I need all new tires?
Posted by PutridSkill5695@reddit | askcarguys | View on Reddit | 16 comments
I have a 2025 Mazda 3 Turbo AWD. I need to replace my front tire, due to the sidewall being damaged. To my understanding, in awd cars you should not have more than 2/32" in difference. My Fronts are 5/32 and Back are 8/32.
Do I need to replace all 4 tires or can I get away with the front 2?
I checked the owners manual but it was no help. TIA
MysticMarbles@reddit
You've already been failing to do rotations and are beyond spec.
Replace 2, new ones on the front, don't rotate until they are 1/32nd below the rears (will likely all wear out at the same time)
No_Win7658@reddit
I will never get the point of rotating
Hungry-Job-3198@reddit
When rotations are done at regular intervals you can get triple the life or more than if you don’t rotate them regularly.
No_Win7658@reddit
I don’t see how this can be true. It just sounds like a way to extend the time you have until you have to replace tires, only you have to replace all 4 then instead of just 2. Rubber loss is going to be constant. My last cars had different sizes front / back anyway - but I don’t see the point. Magic doesn’t exist
Hungry-Job-3198@reddit
You’re right magic doesn’t exist. Almost 30 years in this business, it’s not magic. A little google search will show you. The fronts wear faster than the rear. When they are not staggered like your vehicle has and are all the same size. When you rotate them you balance out the outer wear that happens more in the fronts. I’ve seen a ton of customers get 80k-100k miles out of a set of tires because they rotated them. When people don’t rotate their tires they get 20-25k miles at most normally. You’re right it’s not magic, it’s physics and has been proven for generations.
MysticMarbles@reddit
Vehicles handle significantly more predictably when all tires are worn the same as well. I could never understand having mismatched amounts of traction when 20 minutes every 10,000km solves the issue. Not to mention balancing out camber wear on certain vehicles. Plus it's usually way cheaper to buy 4 tires instead of 2. Same labour cost just half as often, plus it's hard to not buy a set of 4 tires on sale. Then you have stability control issues with mismatched sets. Screw AWD differentials, stability control is going to start intervening for no reason with 1 half worn and 1 new set. You may not notice but it'll be doing gentle brake applications mid corner which is a whole other wear set and cost, however minor.
No_Win7658@reddit
Ok so the real reason here is uneven wear. I used to have that- but ever since I’ve been zit bmw and Porsche it’s always been pretty perfect - except one because it was a runflat gen 1 and overheated
generic2022@reddit
Best practice: replace all 4
2nd best practice: replace both tires on the same axle then rotate tires to put newer tires on rear axle.
AlaskaGreenTDI@reddit
Putting the new tires on the rear in this case would just screw up any opportunity to ever rotate them and would soon have them in a worse off scenario of difference between front and rear than they’re in now.
generic2022@reddit
Mazda disagrees:
https://www.ramseymazda.com/blog/2016/march/10/mounting-new-tires-front-or-rear-it-makes-a-difference.htm?srsltid=AfmBOoq1ouPaAVOoJ_DGc2UU6p6_PplAlqUHZGiiw4SqOBJbrAG5dDLz
Michelin disagrees:
https://thetiredigest.michelin.com/every-day-if-you-only-change-two-tires
https://www.youtube.com/watch?v=HdSf0KJie_E
Goodyear disagrees:
https://www.goodyear.com/en-us/learn/replacing-only-two-tires
Consumer Reports disagrees:
https://www.consumerreports.org/cars/tires/should-you-always-replace-car-tires-in-pairs-a1061792056/
Discount Tires disagrees:
https://www.discounttire.com/learn/replacing-2tires
Tire Rack disagrees:
https://www.tirerack.com/upgrade-garage/where-to-install-new-pairs-of-tires?srsltid=AfmBOorHcqylnHIgq6x7rOub1opAIkT9WQShQFTjMR9cnrU2JM0E0bhD
Tire Review disagrees:
https://www.tirereview.com/always-install-two-new-tires-on-the-rear-axle/
https://www.youtube.com/watch?v=KkFHYYruWSA
Tire Mart disagrees:
https://www.tiremart.com/blog/where-to-install-two-new-tires-on-your-car/?srsltid=AfmBOoom6dWyJOd6efj5cd3tM9QO92UfoE26FhPHZkirSoXPrizxO6wq
youdidittoyouagain@reddit
All of your links are speaking about traction, more specifically wet traction. What everyone else is talking about is the AWD system and how unmatched tires will cause overheating in your differentials and led to failure of the AWD
generic2022@reddit
Most all tire manufacturers, most all vehicle manufacturers, and most all tire service centers agree that passenger cars and light trucks (which includes SUVs) should have new tires mounted on the rear axle when only two tires are replaced.
This recommendation applies regardless of whether the vehicle is AWD or not.
The concern is that if your front tires grip the road better than your rear tires, this can lead to a fishtail.
A wet road exacerbates this well-documented vehicle handling phenomenon, but it remains true regardless of the road condition and the passenger car's or light truck's configuration.
AlaskaGreenTDI@reddit
Except there has to be an ounce of pragmatism applied, and recognize that in this instance the rears at 8/32 are basically same as new, so there isn’t some odd danger of the rear breaking loose before the front.
Also with this misguided application of the “best always on rear” rule, if someone installed four new tires, waited a few months until there was enough wear on the fronts to become evident, even say 1/32, now the fronts are 9 and the rears are 10 still. Cool, almost the same as this exact instance. That person wouldn’t be allowed to rotate their tires now because moving their now 10s to the front and 9s to the rear would also be against the better on rear concept. It just doesn’t make sense to apply it to like new and near-same depth rubber. If OP was going to end up with new ones front and 3/32 rear, then that’s what the industry standard is actually supposed to prevent.
Any_Web_1784@reddit
Prob rotate your tires a little more often so they wear closer to even
djltoronto@reddit
What do you mean by, the manual was no help?
This exact scenario is presented in your manual..
Obviously best to replace all four, but if you only have a 2/32" delta, you are on the limit of acceptability.
It is up to you how much risk you want to take with respect to warranty coverage in the future.
There exists tire shaving services for this exact scenario. You can just buy two new tires, and have them shaved down to match the exact tread depth of your existing used tires
tetsuo_and_soup@reddit
Theoretically you'd need to replace all 4 and im sure thats what most people will tell you, however I highly doubt only 2/32nds difference will cause any real problems, especially on a part-time awd system like yours. Just make sure you rotate them often from now on to try to even out the wear. I do every other oil change on mine.