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What the Tank said.
Hey tank!

"What the Tank said.
Hey tank!"

he talks to a tank...... i knew a man who talked to his car..
it even answered him..." A door is ajar",,,,, it is not.. it's a door....

YO the tank answers? whoa we are in trouble, some doctor is going to make a ton of cash on us.

I think depends on how warn your tires are, if they have a lot of wear and miles on them then yes buy all four, but if need be you can get away with 2, it will not hurt axle. I would make sure you get them rotated and balanced that will help.

If you rotate your tires as is recommended your tires will be worn evenly and thus wear out at same time. Unless of course you have a wear pattern that tells you different, wear on shoulders (toe in) wear in center (tire inflation) flat spots (hard breaking).
And of course the dealership is going to tell you that (they sell more tires that way) However if you are going to buy two tires at a time put them under the most weight. If you own a front wheel drive car this is twice as important as your steering is involved. Never change just one tire on an axel, as this will cause your struts and shocks to carry an uneven load an cause control problems. But like I stated above if you follow rotation procedure you will wear out all four at the same time. Unless a road hazard get you.

I don't think it is the axel that is the problem, but the frame.
It might tweak the frame, and the BIG word there, is MIGHT!

mine is two now and two later.

They are just trying to sell you 4 tires instead of 2!! I've done that (buy 2 for front or back) many times and it didn't hurt a thing. May depend on what type vehicle it is.

I usually only get two at a time.. unless they are all really bald!

Two at a time, unless I really need all four.

You want to keep the two on the same axle, for proper wear, and of course proper handling.

If you need all four, do it, but I prefer not to spend that much money at one time. Usually, the front will wear more than the back. So, put the new ones on the front, this also helps handling of the car. And, always get an alignment if needed.

There is absolutely no chance of two new tires causing damage to the axle, or jeopardizing your safety. Sounds like a sales technique.

One thing to be aware of though is the size of the tire. Get the ones the owners manual recommends. I know the 18"-24" rims/tires are really in right now, but the vehicle was NOT engineered for them. They will cause axle, tie rod and other damage over time. Not to mention that the axle works in concert with the transmission. I would be cautious in that area.

As what they said is that if you rotate your tires every 3.000 miles then you should be fine, but it does depend on your tires if they are warn down and the back ones are fine then buy two new ones and put the new ones in the back and the back ones in the front.

If only buying two you might want to look at this/ It can be done and is sometimes necassary but beware of how you do it. http://www.discounttire.com/dtcs/infoTiresRear.dos

I go by how worn the tires are. Really the main purpose of rotating your tires is so they all wear out at the same time. Supposedly it's for balance. I usually replace my front two tires when needed, and later when the back tires are ready - I'll replace them.

what is an axel? hahaha

the answer is yes... and no...
it really is simple if you think of it.. tires of a different size will roll a different distance with each revolution....
if you have a one wheel drive or a two wheel drive or a 4 wheel drive you need matching size tires... imagine a wagon with three wheels the same size and one smaller or larger,, it will cause all kinds of trouble.. it will try to drag the body of the wagon more or less distance with each revolution... out of alignment,, poor handling... drifting.....
now... imagine a wagon with all four wheels the same size.. smooth driving... good handling.. if you have a regular car or truck one or two wheel drive you need the same size tires on the same axle otherwise one will pull a different amount...more poor steering...
if you have a four wheel drive the problem doubles , if both smaller wheels are on the same side you will be headed for the ditch ...or the center line...
if you must have different size tires,, make the difference as small as possible and put the same size on the same axle.. either axle but the same size...
it is always best to have four identical tires. you will buy fewer tires over the 50 or 60 thousand miles you can get with identicals...
i do not sell tires,, i am a retired carpenter and had to spend hard earned money for tires... i found out the hard way... what happens.... ask your friendly mechanic to explain the spider gears..... it will scare you... but you need to know..