If you buy 2 new tires and put them on a car that has 2 old tires, do you put them on the front or back?
Car is FWD
2 old tires are the same brand and 2 new are same brand, but new and old are different from each other.
The 2 old tires are still in good condition.
So… front or back? And does season affect your decision?
The tire places say to put them in the back. I personally would put them in the front as long as the remaining ones have good tread. Based on the explanations from the tire people I think they assume the remaining two tires don’t have much tread
Put the new tire on the front.
The front tires wear out quicker.
Second if you do have a blow out with the old tires you want them on the back a blow out on the back is a lot more controllable.
You should always put your best tread on your steering tires so that means put them on the front.
The standard answer is put them on the back. Understeer is easier for a poor/inexperienced driver to control vs. oversteer.
For our RWD vehicles, we put the new tires on the front, older tires on the back. Tire places don’t want to do it, and we’ll sign the waiver for it. I don’t take much stock in the tire place’s knowledge anyway, considering they often overtorque the lugnuts…
Season doesn’t change for me because I’m in the deep South, so I cannot advise much on winter driving.
The suggestion for the rear is to cover their asses. It is the correct thought, as oversteer is harder to control than understeer. This is more important with winter tires, as the rear tires of a FWD car need to be as good or better to keep the rear behind you. The thought there is if you cant even get going, can you safely stop, and the correct process is to use 4 snows.
Now what I do, and what most will do is balance the wear to minimize cost, and this means toss em on the front. Talk to the driver and be done with it.
but oversteer is more fun:D
Thanks for the responses. This is the info I wanted.
I can think of no argument for this statement 
the axle getting the power and/or steering should receive the best tires out of the set. Car is worthless without traction. Put newer tires on the front of a FWD vehicle.
To this point, lets assume 2 new tires and 2 tires at 2/32" left. With the new tires on the front, in the snow, you can get going no problem. The issue comes when you go to make a turn and the rear of the car slides out due to poor traction. If you try to stop suddenly, the rear of the car will break traction sooner than the front, and it cannot push the car so it will move laterally and the rear will slide out.
All of this is minimized when you rotate the tires properly to balance the wear, as you will never have 2 bald and 2 good. I strongly suggest that people get a tread depth guage and keep track of tire wear, it is very telling of the vehicle, and only takes a minute to check.
On a front wheel drive vehicle I would much rather have the bald tires on the rear. I find it very easy to correct a skid with good tread on the front driving tires.
How do you handle stopping if the rear of the car swings out? We have tons of hills around here, so this isnt always an option.
On the flip side to that (with two worn tires in front and the new tires in the rear), The issue comes when you go to make a turn and…the car doesn’t turn and instead the front end just pushes straight off the road into the ditch.
Besides planning your tire placement around the presence of snow makes little sense to me (I’m from the south). If you live in an area that gets very much snow, get snow tires, otherwise you’re pretty much screwed anyway you slice it on snow. If I’m going to be concerned with the weather (especially since it is now March), I’m going to be more concerned with wet pavement, which is nowhere near as bad as snow.
I would think about the forces being exerted on the tires and what they are expected to control. The front axle in FWD vehicle has to deal with forces from acceleration, braking, AND turning (usually some combination of the three). The rear axle is just along for the ride! Sure it has to deal with the accel/decel/turning forces to some extent, but not to the same extent as the front as it is the one actually accelerating & turning the car.
As others have suggested, that (understeer) is easier for most drivers to correct out of than oversteer.
I would think that if your tires are bad enough to worry about your car spinning out, you should be replacing all 4. If all 4 tires are in good condition with 2 being a bit newer, I see no reason to ever put the 2 old ones on the wheels that see more wear, unless you are a tire salesman and want to sell new tires to your customers sooner.
I think it was Car & Driver that went to Michelin’s testing facility to test this because they received so many questions about it over the years. They did tests with different drivers in FWD and RWD cars under different driving conditions. All of the testing confirmed what Michelin told them beforehand: the best tires go on the rear, regardless of vehicle. Like others said, understeer is easier to correct than oversteer. I’ve witnessed two accidents on the interstate in the last couple of years, and both involved drivers in front wheel drive cars that had the rear end break free in a curve. I don’t know their tire situation, but it definitely reinforced the opinion of putting the best tires on the back, even on front wheel drive cars.
What was the condition of the ‘bad’ tires in the test? Bald or just a lower tread?
Easier to correct - yes.
Easier to induce - no.
I can’t count how many times I’ve applied too much/too many inputs and overpowered the front tires resulting in understeer in normal driving (albeit mild understeer). But I can remember exactly how many times I’ve induced too much oversteer - ONCE - and it was on the track, not the street.
Having autocrossed a FWD car, it took some REAL shenanigans for me to get the rear too far around that I could not correct with a little throttle. I’ll stick to keeping the best tires on the wheels doing the most work. 