I found this video which shows why you want to put two new tires on the rear.

http://www.thetirewarehouse.com/carcare/mountonrear.wmv

 

didn't know, thanks!

 

I found a higher quality version of the same video. It is availble via the link at the botton of the following page;

http://www.michelinman.com/care/buy_how.html

 

I worked at Sears in the auto parts when Michelin first came to the US with radial tires. People would not believe the salesmen/woman when they were told to put the new two on the rear. Since Sears WOULD NOT put two on the front more than one person walked out without buying tires thinking it was some kind of trick or something.

Earl

 

I had always wondered about the reasoning behind that. That video makes it perfectly clear.
Thanks for posting

 

This should also convince you to never rotate tires on a FWD car.

 

I hear ya. But I'll still be rotating the tires. It encourages even wear which not only increases the life, it also helps to keep them quiet. When all four need to be replaced, I can try another brand, furthering my ongoing efforts to find the "right" tires to meet my needs.

 

I do see a reasoning behind why you shouldn't rotate your tires but what if you rotate your tires pretty often? Like say every 3k miles?

Wont necessarily increase the tire life if you rotate the tires. You'll still get the same amount of miles on the tires, you will just be replacing them at different times if you rotate instead of all at once.

 

The theory is that it will minimize any uneven wear that results from the different demands placed on a tire at each of the four positions. Whena tire begins to wear unevenly, that wear pattern can accelerate, resulting in the premature need for replacement. And, uneven wear paterns do result in tires becoming louder.

None of these things, taken alone, is necessarily a dramatic reason for deciding to rotate the tires. I'll just do it every 5K when I change oil/filter. Everyone has his/her own ideas about how much maintenance is right.:smile:

 

This is a load of bunk, stemming from the same reasoning auto manufacuters build massive amounts of understeer into their vehicles. They expect the nut behind the wheel to be a driving moron and reason there's more frontal collision protection than side.

Unfortunately, the above is generally true, but it gripes me that they're passing the lesser of two evils off as an ideal. Don't you find it odd the video didn't compare stopping distances or traction in snow? The vehicles used for that video were front wheel drive. Most people freeze (bad), lift (worse), or brake (worst) when the tail steps out. In the latter two conditions, weight transfer to the front of the vehicle exacerbates the situation. A trained, experienced driver could have added throttle and negotiated the turn.

Placing the newer tires on the rear will help avoid the scenario described in the video. It will also increase stopping distance in wet weather (not too hot in panic situations) and reduce mobility in snow.

The solution is driver education. And frankly, I think they're idiots for sticking their necks out. By telling people what to do, they've assumed a legal liability. I wonder how long it will be before the TireRack or a manufacturer gets sued because someone put the new tires on the rear and couldn't stop in a panic situation.

Brock

 

Doesn't this video just reinforce the fact that an understeering car is a safer car? I assume that putting the new tires on the back causes the front to loose traction first, which is by definition understeer. So we should all take off the stiff, aftermarket rear sway bars we've added?

 

I was thinking the same thing when first reading this. I didn't respond because I'm no expert with this stuff. I remember the day I read that on a front wheeled drive car you can stomp on the gas and not spin out. Some guy was saying to keep the nose pointed where you want to go and the car will bring you there if the throttle is correct. Later that day I went to the mountains and gave it a try. I can say it worked for me, not in a Mini but a DelSol. Granted these corners you can't take faster then about 40 -50 mph; none of the long corners like in this video.

Brad

 

Excellent !!!

 

Yes, it would be interesting to see a battery of performance tests vs. only one that demonstrates their position.
It also seemed a little strange that the dark car was really losing it, while the white car, at the same speed, appeared perfectly stable. I suppose that could be explained by having more weight on the front tires, but...

 

You got that exactly backwards! You will be replacing them at the same time if you rotate!

I'm sure that's what you meant -- just wanted to make it clear for others who might be reading this thread.