lloyd right

Hey everyone, I changed all four tires one year ago to date and last week I realized my front right needs to be changed. Now i'm tinking of changing all four tires, but the back ones are rarely worn out for sure as I only drove abouto 8k miles over the last year. What are the main risks if I just change the two front tires? THat's what I intend to do. I don't know if the tires being staggered matters in this case, but the back are wider and usually always in better condition than the front. In fact, the back rims are rarely dirty as most of the braking is done at the front. THanks for your help.

W205C43PFL

Do you have 4MATIC? If you do definitely change all of them to prevent putting additional stress on the transfer case, recommend having same brand and model and same tread remaining.

GJC400

Just because you have 4matic, you don't necessarily need to buy all 4 tires if the 2 you'd like to keep are on the same end of the car and within 4/32 (i think) tread life of the new ones. You'll want to confirm the measurement, but there is a tiny bit of leeway when comparing fronts to rears. I had to replace my rears only, and the shop told me they wouldn't install them if the difference between old and new was more than 4/32. The difference on mine were less than that. so I put the 2 on the rear and everything has been great after 2 years. I don't think the same applies if, for example, your left front needed to be replaced but your right front was fine. In that case I think you need to do both right and left.

Keith66

If this were my scenario, I'd replace both front tires and everything will be fine. In fact, if you are only replacing 2 tires out of 4, you would want the new tires on the steering axle anyway, so you're good.

I understand people being hesitant adding any differentials of measurements to AWD cars, but I don't believe modern AWD systems are nearly as sensitive as they are betrayed to be.

If you really think about it, if manufacturers made AWD systems that fragile, there'd be dead AWD cars littering the side of roads everywhere, lol.

Also, who knows anyone that has ever had a modern AWD system grenade itself because of dimensions? I surely haven't. I hear a lot of people and mechanics make reference to it, but I have yet to see a proven example of it.

JMO.

Good luck!

W205C43PFL

My bad, thought OP said the left front and left rear was wearing, shouldn't be a problem if it was on the same axle, good catch.

W205C43PFL

I mean personally I never seen any fail catastrophically either but better safe than sorry, there might be additional wear, so it adds up over time. There is reason why it is recommended to even shave tires with significant tread difference if not removing them all if the problem is on the same axle. That is just what I heard That said though, I mistakenly read OP as having front left and rear left tires having issues, so there is that too.

lloyd right

Thank you,

I just wanna know I won't destroy anything or die on the road for trying to same some cash.

W205C43PFL

For sure OP, safety first! Enjoy your ride

Keith66

Sometimes the correct answer is not always the right answer. It may be more about what you are comfortable with.

You are obviously concerned, so I would recommend for you that you replace all 4 tires. Otherwise it's probably going to stay on your mind and drive you nuts, lol.

Personally I think it's not an issue to replace 2 tires on the same axle and again I sure would like to see some proof it could be an issue (not just an old repeated wives' tale), but you really should listen to your gut.

Keith66

And just to add some color to the conversation, of the w205 4matics shipped from the factory with staggered wheels/tires, most of the rears are a smaller diameter than the fronts by about 0.3 inch. That's an approximately 19/64ths of a difference front to rear.

lloyd right

TBH, once I drive it and I don't have any issue I won't even think twice about it thereafter lol I just wanted to know it's not going to damage the car.

Keith66

Cool, then replace the 2 front tires and be happy that you didn't needlessly spend ~$500 replacing good tires. It's not going to damage your car.

I'll add one more thing and I'll stop beating this dead horse... this is a fairly large message board encompassing all Mercedes models and has been online for many years. If this was a real issue, it would be expected to see a multitude of threads and posts filled with the 4matic horror stories of massive (or even slight) failures caused by people running new and "old" tires, mismatched tire pressures, etc., but nope, crickets.

Unless a mismatch in tire tread depth causes piston failures also, lol.