Is it safe to run new tires only in the back?

[icybrzzz]

Originally Posted by EndlessAzure

If you can avoid it, don't mismatch tire compounds front-to-rear.

From personal experience, what @soundman98 says is true. Yes you can drive the car, but the TCS system is going to be very active and the general confidence of the car is going to suffer.

I had a puncture in one of my tires and was running mismatched compounds for a while until I had a chance to replace the tire. I used Hankook Ventus V12 Evo2 and Federal 595 RS-RR, both same size (245/40R17) but paired on different axles. The TCS was way touchier than it should be, and triggering a lot when it didn't used to. The car overall felt more "floaty" and vauge on corners as well.

I've been running Yokohama A052 235 fronts and Primacy 215 rear with no issues lol

[ItsReiko]

Thanks for the comments guys. But I wanted to clarify that my initial question was about putting the same exact model/compound/size tire in the rear that is just worn differently than the fronts. Not a completely different model of tire.

I would also assume it's not the best to run a different compound front to back.

[churchx]

Depends your level of safety requirement. People do stupid things for looks and get by with it with generic daily driving, especially if leaving sufficient safety margin for unexpected. When you get closer to limits, eg. on track, or during reduced grip, such as when wet or in winter on ice/snow, though sometimes also on normal grip pavement during some emergency maneuvers, bad things to handling/suspension/braking/grip & grip balance/working of safety nannies may surface rather easy.
Still, due LSD diff, always worth to have in rear as similar tires as possible. In your case, if punctured rear is not repairable, if very budget strapped, put front tires in rear and get one new tire to be used in front. Or get two, and use both new in rear or other way around, both in front.
Many punctures are repairable in tire shop .. unless emergency repair gunk is used on them or there is structural damage to tire sidewalls. Reason why one of my first "mods" was replacing stock tire repair gunk with spacesaver wheel. Win-win, cheaper fix/repair, and same wear level.

[soundman98]

Originally Posted by churchx

Depends your level of safety requirement. People do stupid things for looks and get by with it with generic daily driving, especially if leaving sufficient safety margin for unexpected. When you get closer to limits, eg. on track, or during reduced grip, such as when wet or in winter on ice/snow, though sometimes also on normal grip pavement during some emergency maneuvers, bad things to handling/suspension/braking/grip & grip balance/working of safety nannies may surface rather easy.
Still, due LSD diff, always worth to have in rear as similar tires as possible. In your case, if punctured rear is not repairable, if very budget strapped, put front tires in rear and get one new tire to be used in front. Or get two, and use both new in rear or other way around, both in front.
Many punctures are repairable in tire shop .. unless emergency repair gunk is used on them or there is structural damage to tire sidewalls. Reason why one of my first "mods" was replacing stock tire repair gunk with spacesaver wheel. Win-win, cheaper fix/repair, and same wear level.

One should always put the higher-tread tires in the rear. So in a case of rain or snow low traction, the rear tires have more grip. More grip in the front means the potential for the car to desire to swap ends at the least desirable time.

The consensus from the links I provided is that a significant difference in tread depth front to rear makes the cars safety systems more prone to activating. The level of activation is going to be somewhat speed-dependent due to the physics of circumference. If you're only going to be using the car at low speeds around town, it won't matter all that much.

But higher speeds on the highway, the system will likely not be very happy

[grumpysnapper]

Originally Posted by soundman98

One should always put the higher-tread tires in the rear. So in a case of rain or snow low traction, the rear tires have more grip. More grip in the front means the potential for the car to desire to swap ends at the least desirable time.

Ive always felt that the front wheels have the greatest potential negative consequences...%80 of the braking and all of the direction.

[churchx]

grumpysnapper: well, you should know well from your type of driving offroad, the less there grip is, the less mass transfer happens and "right" brake bias moves proportionally in direction closer to 50:50 (and opposite, if more grip, eg. stickier tires, more aero). Not just on gravel, but also in wet, or in extremes, on snow/ice. Then again i wouldn't understand those that switch off nannies when driving on public road, for ABS/EBD/SC to not help fix somewhat grip bias issues. Also IIRC EBD programming is rather understeer-ish (which for some trailbraking on track is unpleasant thing), so should do well even a bit more front biased grip.

[Overdrive]

Originally Posted by soundman98

One should always put the higher-tread tires in the rear. So in a case of rain or snow low traction, the rear tires have more grip. More grip in the front means the potential for the car to desire to swap ends at the least desirable time.

While I understand where you're coming from, my thoughts and experience are of the opposite when it comes to driving in winter conditions on winter tires. I prefer to have the tires with more tread available mounted up front to have more control over the wheels that are steering if/when the car gets upset. My caveat here is that one should never really have such a difference in wear between front and rear tires that you have a severe difference in tread wear and grip. They're a maintenance item just like filters and oil that need to be checked and rotated regularly to avoid severe uneven wear.

Anyway, if the rear starts doing any sort of unwanted movement on me in a low traction environment, I immediately go to correcting it with steering and limiting throttle inputs. With all the nannies on (I don't take chances when there's snow), the car is going to be doing its best to reign in any wheelspin or sliding so I can focus on keeping the car pointed in the right direction and/or coming to a stop. When this happened to me a few years ago I would not have had as easy a time keeping my car on my side of the double yellow line if my front tires were more worn than the rears. The nannies stopped the rear yaw and I had plenty of bite up front to keep the car pointed straight and staying out of the oncoming traffic lane.

After a few seasons, and seeing where the tread depth is on the rears compared to the fronts, I'm likely replacing that rear pair, and the slightly worn tires that were the fronts get moved to the rear.

As for the rest of the year on grippier tires, I try to keep up on regular rotations and maintaining tire pressures so that they wear as set. How worn they are would dictate if I'd replace a pair or the whole set if I had a puncture or failure.

[jflogerzi]

Originally Posted by icybrzzz

I've been running Yokohama A052 235 fronts and Primacy 215 rear with no issues lol

Wait what why???? Don't you want that reversed....

Sent from my GM1915 using Tapatalk

[icybrzzz]

Originally Posted by jflogerzi

Wait what why???? Don't you want that reversed....

Sent from my GM1915 using Tapatalk

I prefer front grip vs rear, the front does all the turning and most of the braking. This is my "drift" setup btw not my track setup lol. I find it much easier to drive with more grip in the front vs the rear.

I was driving around with basically bald A052s in the rear and it was not a problem. Even in the rain i'd only run into issues when I passed over puddles with the bald rears, otherwise the car felt very planted