drchpeteros

2009 E350 4matic wagon.
Is there any reason I can't replace one tire. Tire cannot be repaired, and I'd rather not buy 4 (if I have to I will). They have 20,000 miles on them with a little life still in them. Can I replace the one with a used tire? Additionally, if I do have to replace all 4 does anyone have experience buying used tires?

rapidoxidation

If you want someone else's (unknown) tire history keeping you glued to the road, go for it. That's a level of risk I don't care to accept myself, but YMMV.
As far as replacing only one and not all four, if you make sure the diameter of the used tire is the same as the other three (and the size is the same and hopefully even the make/model) then it shouldn't mess with your 4matic and speed sensors too much. If that diameter is too far removed from the rest of the tires though, your car will not be happy because that wheel will be turning faster or slower than it should be.

juanmor40

Over the years, when I am in that situation: one tire is not repairable, but there is still life in the other 3 and in a pinch, I always replace both tires on the same axle and move the good used tire as a full-size spare instead. Not a chance to have different tire patterns on the same axle and very different diameters (on top of @rapidoxidation remark).

Once the pinch is gone, and how the particular vehicle is used I will proceed to update the other two remaining with tires of the same specifications as the newer ones (barring you do not have staggered sizes)

cetialpha5

I would go as far as to say you should use the same type of tires as a replacement one so you don't have a different spec tire on each side of the same axle. Different brands will have different stopping characteristics and tread patterns and even though the size is supposed to be the same, they may be slightly different between manufacturers. You also need to know how to look for problems in an old tire, cupping, too much wear on one side vs the other, inspecting the inside of the tire for previous patches. I think you can patch a tire once but I wouldn't want to buy a used tire that already has a patch. And then there's the usual places, craigslist or facebook marketplace or eBay. There's also some used tire vendors that sell on Craigslist that will have more variety.

But in the future, OP should just get tires at Costco, they have a 5 year free road hazard warranty and then he can either keep one of the old tires as an emergency spare in case Costco has to order a replacement or he can just sell the other 3 good tires on those sites mentioned before.

Typically they say for 4matic you should have the same tread depth on all the tires, but I think Mercedes is a little more forgiving than BMW or Audi 4 wheel drive systems. Not sure exactly how much of a variation you can have as it never really gets mentioned.

hceptj

OP, why don't you go to a MB dealer and ask them about the wear difference allowed? Last time I checked, going to court and saying "the guys on the MBWorld forum said..." isn't going to fly as proof. However, a note or repair guide from MB would qualify.


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juanmor40

I definitively agree with the comment, but dealers are not HQ representatives by any means of the imagination; therefore MB will ignore and stick to whatever the want in court.

The typical MB dealer's answer too advice is buy new everything since they do not know what an used part can do their sofisticated designs and pay through the nose..

MB = pay to play