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This question already has an answer here:

As the titles says I've seen several shops indicate that if you can only replace two tires that they should go on the rear, example Firestone:

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So shouldn't tires be placed on the front? I was under the impression that if your older tires were on your front you would loose traction if trying to turn in a rain storm. Another issue I would imagine is braking would be effected since you have greater of percentage power in the front?

Also referenced:

The purpose of this Q&A compares to the above two was to get a better answer on why the rear is preferred to the front. The voted question that is being considered as the duplicate of doesn't mention oversteer.

marked as duplicate by MooseLucifer, DucatiKiller, I have no idea what I'm doing, Nick C, Pᴀᴜʟsᴛᴇʀ2 Apr 29 '16 at 13:34

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • I prefer them on the steering (front), a blow out on the front is much worse than the back, I keep the best tires on the front, there is no set rule and have heard both sides of this question. Tire shops always advise the opposite, I suppose its a corporate lawyer thing, they figured the odds on blowout vs hydroplaning. – Moab Apr 28 '16 at 18:19
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    For those who get here from Google or casual browsing, this question isn't really relevant to AWD vehicles. If you need to replace tires on a vehicle with AWD, you are either shaving the new tires down to match the tread depth of the other tires you are keeping, or you're replacing all 4 tires. Either way, it won't really matter where the new tire(s) go. – Ellesedil Apr 28 '16 at 22:14
  • @DucatiKiller: As you were one of the mods marking this question as a duplicate: Shouldn't the duplicate marking be the other way round. This question and answer seem to be far higher quality than the marked question. Per meta.stackexchange.com/a/10844/184432 – David Mulder Nov 7 '17 at 18:42
  • @DavidMulder I think the key point is the last line from the link you posted "If in doubt, close the more recent question as a duplicate." It's safe to do. – barbecue Nov 8 '17 at 21:55
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Officially, the better tires go on the rear to help prevent oversteer. If you front tires loose traction (understeer), you are going to go straight until you catch traction, or hit something. Its safest to hit something with the front of your car. If you oversteer, it is much more difficult to recover. You are more likely to hit things with the side or back of your vehicle.

If you are a bit more experienced, and your tires aren't bald to begin with, having the better tires up front isn't too big a deal. The rear typically has more negative camber to give it better traction. You typically will not have issues as long as you aren't pushing your tires to the limit. However, you will be more likely to loose control in an emergency braking/avoidance situation.

Personally, I run the better tires on the drive wheels. I drove a FWD car for years with sporty 225s up front and all season 195s on the back and never had an issue.

  • Good answer +1. On the other end of the spectrum, I had 205 a/s all around on my old FWD car. I made the mistake of lifting off the throttle in a sweeping left hander at ~50 mph and found myself backing through a shallow ditch before I knew what was happening. – MooseLucifer Apr 28 '16 at 23:28
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As you may well know: when you're turning, an under-steer condition is when the front tires lose grip and start to slide, and an over-steer condition is when the back tires loose grip and start to slide.

For the inexperienced driver, under-steer conditions are much easier to control, as you can still see where you are heading, and can simply straighten the wheel to regain traction and attempt to control the vehicle.

Over-steer conditions are much more dangerous, because the yaw rate of the car when the back tires lose grip will cause the car to spin. This not only makes the car much more difficult to control (attempting to steer becomes frantic and confusing when you suddenly find yourself traveling backwards), but also makes it hard to see what potential obstacles you are heading toward.

Over-steer conditions will be exacerbated if the front tires have significantly more grip than the rear, as they will allow faster corner entry than the low grip rear tires can't handle: resulting in a spin. Hitting the brakes will also shift the weight of the car onto the front axle, increasing their potential for grip while simultaneously decreasing the load and grip on the rear axle, meaning any movement of the steering wheel will have a higher chance of causing the rear tires to lose grip.

@Moab is probably correct in assuming lawsuits against tire shops for outfitting new tires on the front forced this rule, despite the fault likely being the drivers for traveling too fast for conditions. Either way, if you feel strongly otherwise you are always free to rotate your own tires when you get home.

  • However, the factor of "too fast for conditions" is lessened by putting the Good Tires in the Rear. That's why shops might be held liable for making the vehicle less recoverable from driver errors experienced by common drivers. – user12711 Aug 7 '18 at 17:13
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It really depends. If the car is front wheel drive, then you are expecting your front wheels to do all of the following well:

  • Apply power to the road
  • Steer
  • Do the bulk of the stopping

Sounds like you would want the newest and best tires on the front.

In a rear wheel drive car, if the front lose traction you're going to under steer in a wet corner. (If you're not familiar with it, under steer means the driver turns but the car just goes pretty much straight.) If the rear tires let loose in a corner you will over steer. (The driver turns and the back end comes out making the car steer more than the driver intended). If I had to chose, I would take over steer over under steer any day. With over steer in a rear wheel drive you can control the amount of turn in with the throttle. With under steer, once you are in this state, you can't really slow down because the front wheels are already sliding so you can't expect them to provide good braking.

Honestly, maybe it doesn't matter, I would suggest you put the good tires on the front. Which is exactly what I believe long haul truckers do. They may have retreads on the rear wheels of the tractor, but the fronts are always nice new tires.

Hope that helps!

  • FWD cars can still lose rear grip in a wet corner, and when they do you have zero options (as opposed to RWD like you mentioned, where you can steer with the throttle) – MooseLucifer Apr 28 '16 at 19:33
  • I have never tried it, and I don't recommend anyone do except under safe conditions, but I have always wondered in a FWD car, if the back end breaks but the front still has grip, would adding power help pull the back end back in? The pulling action tending to pull the rear into line rather than hanging out. Always wanted to experiment with that. Maybe on a wet closed runway? But that has the danger of rolling over if you hit the edge of the runway.. How do I know this.. :) – cdunn Apr 28 '16 at 19:37
  • I guess I should say the average (read: bad) driver has no options, otherwise I believe you are correct. The front tires in a FWD car will pull the car in the direction they are facing, which is why FWD is still pretty big in amateur rally/rallycross racing. Not to mention that they are usually much cheaper to buy and run. – MooseLucifer Apr 28 '16 at 20:02
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    Most drivers have zero experience with tires losing traction, so their response is to slam on the brakes, which is really bad when you lose traction on the rear tires in a FWD. I have experienced a "fishtail" after a really quick lane change to the shoulder on the highway (someone stopped on the fast lane to look at an accident...), and I hit the gas hard when I was on the shoulder to regain control. If I stepped on the brakes, I probably would've skid sideways and flipped over on the guardrail, or probably do a 180 and end up facing the wrong way. – Nelson Apr 29 '16 at 2:32
  • @cdunn yes, it will, this is actually taught in driving schools where I live. – I have no idea what I'm doing Apr 29 '16 at 7:16
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It turns out that you do want them on the rear.

And one of the reasons is probably not what you would expect.

It turns out that it's important that the front tires lock up first when braking hard, for example, in wet weather.

That sounds backwards, I know. You might think, I want the rear's to lock up so they hold the rear end back and keep me from spinning. Except, that's not how it works.

It turns out that static friction is stronger than sliding friction. Meaning, normal rolling tires can brake harder than skidding tires.

And more braking in the rear keeps you from spinning, unless you just completely blow it and lock up all four tires. But a lockup is a warning. With better tires in front, say, in the rain, it would be easy to brake harder, a little harder, then a bit harder, and then with no warning lock up the rears and start a spin.

And so, the older tires that will skid first should be in front so they don't hold as well in bad weather, where normal drivers are most likely to brake too hard for the conditions.

  • Are there many cars around nowadays without Antilock Breaking Systems? – Qwerky Apr 29 '16 at 10:03
  • @Qwerky, ideally, the antilock mechanism would limit braking to just short of lockup, but it doesn't work that way of course. (It just pulses the lockup off and on to retain some steering.) I don't really know, but I suppose you still need the front/rear bias to be in the stable zone. I mean, suppose you screw with the front/rear bias by putting new rain tires on the front, and suppose antilock did allow you to steer out of the spin, how many drivers could steer fast enough? – DigitalRoss Apr 29 '16 at 14:55

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