My tire store is the same if only doing two on the rear. is the car fwd or rwd? my car is fwd and if i put the new ones on the front the rear of the car might become tail happy under hard cornering and bracking. plus how is the front end alliment?
The reason for having better traction in the rear is that, in a panic stop, you do NOT want the rear end to swing out and spin the car. And in a panic stop, weight gets taken off the rear wheels, making them more likely to lose traction. So you want the rear tires to have as much good trread as possible.
The front tires, on the other hand, get weight transferred onto them in a panic stop, so even with less tread, the added weight improves the traction of the front tires.
The only case in which this logic is questionable is in the case of high speed driving in wet conditions, when hydroplaning could occur. In that case, the front end is more likely to hydroplane first, so you want good tread depth up front.
Your logic is excellent, however the correct place for the new tires is on the rear. In the typical front wheel drive car, the weight is about 60% over the front tires and 40% over the rear tires. That means that the front tires have about 50% greater weight. Weight = traction. If you place the better tires on the rear, you exaascerbate this traction difference, and in bad weather conditions your rear end can lose traction before your front and swing around, resulting li loss of control.
Testing has proven the theory to be true.
However, I feel I’d be remiss in not pointing out that tire places have gotten carried away with the idea in mandating it for all cars and applications. They should ADVISE the customer, and even POST the explanations, but IMHO the customer should have the right to say “put 'em on the front”.
It’s really a trade-off. You already know all the reasons for placing the better pair up front. But if you drive recklessly in flooded conditions, you have a greater risk of loss of control with that set-up. You give up one set of advantages for a different one.
The tire dealers are worried about their liability if they place new tires up front. Still the decision ought to be left to the car’s owner.
It’s safest to have the best tires in the back. In any slippery situation, if the front tires lose traction first, the car will understeer; an average driver can easily recover from this. If the back tires lose traction first, the car will oversteer and quickly go into a spin; a non-professional driver is unlikely to regain control and is very likely to crash.
I know what the experts say, but I’m still old school, best tires up front. I have had instances under normal braking with the better tires on rear of the front end losing traction and nearly sliding through stop signs, but have never had a problem with the rear losing traction. I also don’t drive like a maniac when the roads are wet/icy/snow packed, I try to adjust my speed to what I feel is safe for my tires, equipment and driving ability. The last time I only bought 2 new tires the other 2 only had about 10K miles on them, I requested the new tires up front and that’s where they mounted them, no argument or questions ask.
There may be a slight advantage to installing two new tires on the back unless the front tires are nearly bald but if otherwise, that is lost when you rotate them to the front at 8000 miles as you should. New tires on the back gets you out of the door to the extent that the trial lawyers are kept at bay for the installer.
A paid auto maintenance person who potentially dangerously rotates almost new tires to the front likely has no knowledge of what happened before and therefore can escape the clutches of trial lawyers. If the owner does his own rotation, he has nobody to blame except himself if he has a crash due to allegedly unequal tire traction.
This “new tires must be on the back” rule is a silly game that must be played by tire installers. It ignores traction control, antilock brakes, traction rating, whether front or rear drive and remaining tread of the older tires.
This question comes up often and I’d like to see more of what respondents here, trial lawyers and tire installers say is supposed to happen after tire rotation.
No one wants to be in a situation where your car has lost it and you have lost control and are looking out the front window and seeing where you have been and not where you are going.
The best tyres on the rear normally will help you get past the slippery areas, but it will make control of where your car is going more difficult. In an emergency most cars tend to loose traction of the rear tyres, causing the car to loose direction control so it takes control from you.
The recommendations for the best tyres in the back is what the professionals who study accidents and do test track studies recommend.
When I need an operation, I choose a doctor and follow his or her advice. When I need car handling advice, I follow the advice of the professionals, even if it does not seem right.
As near as I can tell the recommendation to place two new tires on the rear is based on the following:
New tire are less likely to hydroplane
New tire are less likely to fail due to age and/or wear.
NHTSA tests show that drivers are more likely to lose control of of the vehicle if a rear tire fails. Or " decreasing under steer"