Tire Question
 

Comrades,

I am in the market to replace to rear tires. I prefer buying used ones on Ebay. I have been informed due the vehicle being 4x4 I have to have replaced all 4 tires. Unless, the use timing on the tires are below certain requirement.
Can any one further elaborate on the statement?

I have 2006 X5 4.8is.

not entirely true, if you have above 50% treadlife you can keep. My personal recommendation is to replace all 4 because tires are a crucial part of your vehicle, also if you have different tires with different tread patterns and compounds it can effect the friction between the wheels and road and cause slippage. This can also cause excessive road noise and handling issues. I recommend leaving the tires until you can get a set of 4 of the same tires (dont have to be new just as long as they have a good amount of tread)

You can get a set of 4 tires for the 20's for under 800 bucks, I'd just replace and balance a fresh set, and get an alignment.

I have heard that I must change all four tires if two are worn out many times. I don't buy in. I wear out one set of front tires for every two sets of rears. The only time I replace all four is when all four are worn out.

That approach is important to consider if changing brands as the handling may change (can be better, can be worse) or because the tires may a greater difference in height even though they are designated the same size. IMO, even then it is not an absolute.

you don't HAVE to replace all 4 at once and honestly... if your running a staggered setup, I would only replace 2 at a time ( fronts / rears ) because since your not rotating them, they will not wear out equally.

good luck with the ebay tires and I would suggest checking the dates on em ;)

I am a stickler about handling and having good tires but I don't like to spend tire money for no logical reason. I am not about to throw 2 tires away that have thousands of miles of wear left. I have never replaced perfectly good tires even when I have changed brands and I have no idea how to wait until the other two are worn out when two already need replacement.

I say it doesn't matter what amount of tread your good tires have. If they are good tires there is no need to replace them. You will be fine buying just two if those purchased are a close match to what you have. Just because you are buying used tires it doesn't mean you are making your X a safety hazard.

What tires will you be keeping and what tires are you thinking of buying-- as it relates to brand, model, size and rating?

Hisenberg, I'm with bcredliner & Bigblack on the logic, and can see buying two someone is swapping off their vehicle and selling on ebay or craigslist, especially if you have the 'staggered' wheel set on your X5 and can match at least type tire to the fronts you are keeping [e.g., asymmetrical summer performance, not mixing such tires with all season, etc.]; especially if the wear is close. That said, I'd limit my time investment in searching for/looking at used tires ;).

I just had to buy two new rears for my factory 20's and it took me a LONG time to track down a set of new Michelin Latitude Tour HP to match my 85% remaining fronts.
BUT in the end, I was able to, and I did not have to buy 4 new tires and have 2 fronts in near perfect condition to sell to someone else, or throw out.
So check the usual suspects for used tires and then look at new, just to make sure you're not getting hosed on the used tires prices.

I did say be a smart shopper, you might get a good deal on new tires than used.
used are used and aging matters on them.