g4benz

I called Mercedes Benz. They did not have a clear answer or any answer really as to why the E550 4MATICs do not come with a staggered setup and why some other 4MATICs do. Her only answer was "Mercedes did not build the E550 4MATIC that way, so you should keep it the way it was intended"...I pressed her on this and she simply said that it wasn't "built" that way from the manufacturer...

When I asked her if the 4MATIC system/design had changed, she did not have an answer. She kept reading from the manual. If it wasn't built that way, then don't change it. So, I am not confident with their answer. To me, this is not a "technical" reason. She asked me to call back with the tire sizes on my car, but I can 100% assume she will say "nope, thats an aftermarket setup"..well DUH..

She actually told me to ask the previous owner on why he changed the wheels..and that he would know more about the setup..I then said.."umm..I'm basically asking YOU if the staggered setup will hurt the AWD on the car"..to which she again had no clear response..

very interesting..I will call back with my tire setup for kicks..

ddeliber

Be careful here. The above statement in bold is a dramatic overstatement. Sure your car won't explode when the front wheels spin at a different rate than the rears, but the more the slippage the more wear there will be and the more difference in diameter the more the system slips. I don't believe that anyone here disagrees with this.

I am not going to argue why MB puts staggered setups on vehicles equipped with 4Matic but one thing I can say for certain, no one here knows the real reason. I have seen many marketing/business weenies win design decisions over engineering than you would ever imagine.

The 4matic system MB uses works fine, but it is an older system and there are better designs out there. Clutches have been around for a very long time and it is pretty common knowledge that they wear when they are engaging, not so much when they are all the way in or out. Think about it, when there is a slight difference in rotational velocity between front and back tires the clutch will be "engaging" more often and thus slipping and wearing more often.

Sure clutches are designed to engage, that is what they do, hell every time you turn it engages. But, the concept is not really that complicated here. For me, the bottom line is more wear, more maintenance (and I don't think you can replace the clutch in the transfer case once it goes so does the whole thing). This wear is directly proportional to the difference in diameter between the front and rear wheels/tires. I don't know what an "acceptable" difference is, and unless you are an engineer that works on this system you don't know what the word "acceptable" really means. For all we know, it could mean it will probably last up to the warranty period or the business weenies won that one.

g4benz

So, when is the 4MATIC hard at work? On slippery/snow surfaces? What if it's dry road in the summer, is the AWD constantly working??

ddeliber

The 4Matic AWD system is always "working". Power is delivered 45% to the front and 55% to the rear - at least on the 2012 E-classes, I believe it is the same on 2010s but I am not sure. What I was describing is what happens when the front wheels spin at a difft. rate than the rears. The 4Matic system detects this as slippage and redistributes power to the other wheels using a clutch. It is more complicated than this, but for the purposes of this discussion this is the basic principle.

g4benz

Your reasoning does seem logical. However, what is your explanation as to why some 4MATICs come from the factory with a staggered setup? Are these 4MATICs "special" in some way and staggered-proof? Mercedes Benz could not even answer that question when I called them earlier this morning.

ddeliber

I have absolutely no idea why MB delivers staggered wheels on 4Matics which is why I don't think it is productive to argue one way or the other. I do know that it is not going to help with traction, the 4Matic system trumps anything that the tires are going to give because it is going to transfer the power to the wheels that aren't slipping. The only reason I can come up with is because it looks cooler. I wouldn't be surprised if MB got some feedback like - I went with the Audi because I like staggered wheels and MB doesn't offer this. To which some business guy replied sure, we can do that too. Again, I am not saying this is actually what happened but it is as good a guess as anyone else is able to provide here.

The 4Matic AWD system is absolutely not staggered-proof. I don' believe anyone is arguing this. It is more like - it is not going to hurt "much" if the diameters are "close enough" so knock yourself out. The definitions of "much" and "close enough" are really what people are really arguing about. IMO there really is no value to it so I wouldn't do it, plus you can't rotate front to back and the rear tires will wear out MUCH faster than the fronts.

I honestly don't know what I would do if I were in your situation. I'd say if the diameters are within a couple mm then you are probably fine.

g4benz

Understood. In this case, I hope the diameters are within a couple of mm. I should see my car in the next couple of days. I will post back with the sizes. Thanks.

KEY08

I buy 4Matics to get me through the crappy Chicago winters. In snow, which it seems you will be driving in, the skinny tire always wins. So, in that case going wider out back is for looks only. If you like the look then keep it. If you want to gamble on a $6,000 transfer case then this is your choice. Good luck!

g4benz

Well, I reached out to Renntech for advice, and here's what they said:

I can understand your concern but you have the same transfer case as the E63 so I wouldn’t worry about it.

g4benz

FWIW!

On the front, I got Continentals 245/40/R18 97H

On the back, I got Continentals 255/40/R18 99H

rediesel

Such a small difference between 245 and 255 I wouldn't worry about it. IMO staggard on 4matic is probably OK since the CLS has that setup; that said, I'm not running out to get staggard since MB can take the position it's to blame should transmission i$$ues arise and I'm under warranty. If I had a tuned car out of warranty I'd run staggard.

g4benz

Yep, agree with your thinking. This is indeed a small difference (10mm) and my scenario is exactly what you describe, tuned and out of warranty.

mkrr24

Don't want hi jack this thread, but it is recent so maybe someone will give me an answer.

Is it possible to have wider tires and bigger rims on e550 4matic 2010 all around from 18" 245 original - and if it is what is the most I could upgrade to, without compromising the steering when turning and other mechanical issues if there would be any.

Thanks in advance.

DJ Hellfire

They aren't going to take a "known risk". They actually engineer the vehicles. Taking "known risks" would/could mean they are risking safety, which would not make sense.

With that said, there is nothing wrong running staggered on any awd system. Several other manufacturers in addition to MB, including Porsche and BMW to name a couple, also ship staggered awd setups. As pointed out, as long as the overall rolling diameter is within 1-3% of each other, it will be fine. Saying otherwise is like suggesting that your awd system will blow up if the non-staggered rear tires have more wear than the front or vice versa. Even if you get all 4 of the same size tires, they are never going to be 100% exactly the same size. There's always gonna be some small variance. It's rubber.

I was an ASE certified technician for over 10 years and found that a lot of places created these "scare tactics" to sell more tires. Like telling customers if they replace one tire on awd, they have to change all 4. It's bull**** and a rip off. Like shops still telling customers to change oil every 3k. All for the revenue!!

Arrie

Well, try get your center differential lock repaired under warranty if it wears out or fails when the dealer knows you have been running staggered setup on an E-class...


I know what you mean and it should be fine driving staggered but I guarantee MB will not fix it under warranty if they know staggered wheel have been used.

DJ Hellfire

Legally they have to prove the wheels damaged the vehicle in order to deny the claim. That's the law.

In any case, you could just swap the wheels to avoid the hassle.

mkrr24

Is it possible to have wider tires and bigger rims on e550 4matic 2010 all around from 18" 245 original (front and back)- and if it is what is the most I could upgrade to, without compromising the steering when turning and other mechanical issues if there would be any.

Thanks in advance.

DJ Hellfire

Depends. Running an overall larger (or smaller) overall sizes changes the gearing of the trans and differential even when using the same size on all four. This is also why your speedo would be inaccurate. Probably wouldn't cause issues immediately but I've seen it kill transmissions after long term use. I would advise staying close to the stock rolling diameter.

KEY08

why? There is good meat on the E already. It will alter your turn in and if you drive in snow it will make it more difficult to gain traction. More unsprung weight as well. Is this just for looks?

threeMBs

mkrr24, 255s all around can be used with zero issues. Stock 8.5" or (not wider than) 9" is most preferable. But, FYI 9.5" do fit with careful planning, but is not recommended, thought some here do use it without any issues.

mkrr24

Yes for the look only
I don't like the fact that the original wheels r tacked in so far. I want them flush with the fenders and I want cv3 vossen or niche Milan.or similar
I really would love rwd as it would uncomplicate things- this is what someone suggests for my car 20x8.5 +34***20x10 +40**tire 245-30-20**rear 275-30-20 falken fk-453 - just wondering if this would make the wheels exact- acceptable or not for the 4matic - anyone wants to take stab at it - I'm tired of trying to understand this good bad and so on for 4matic - please help me - all I want is a concave look as deep as possible and not to compromise anything on the car
Thanks good people

Ed99

I ran 20x9 32et with 245/30/20 and 20x10.5 42et with 275/30/20 flush fitment

And

19x9.5 29et 235/35/19 and 19x10.5 36et 255/30/19 some poke

All of the above works fine and I have 4matic. Hope this helps. Your specs you want should be no problems.

threeMBs

Using rear tires .7" taller than front on 4matic is not a good idea (even if some are using it). (Its 3% difference front/rear vs. acceptable 1% front/rear difference, hence IMHO its not the best choice even for RWD).

For best results use 235/35-20 & 275/30-20 (identical 26.5") or 245/30-20 (FYI 245/30-20 does not have proper load for E, so I would use 255/30-20 instead) & 285/25-20.

All above front mentioned sizes do not have proper load for E and especially for 550 4matic. Since your car has airmatic, 245/35-20 should fit front, however in such case 285/30-20 would need to be used in the rear which it most likely will not fit without robbing.

mkrr24

so what would be the widest setup all around 20" non staggered? - width of the rim, tire size and offset for square setup or 19"

Thx for all the answers

threeMBs

The widest safe square set up would be 9" wide wheels with 255/30 and 255/35 width tires (both 20" and 19" respectively) with front 37-40mm offset and rear 33-37mm offset (tha's for fender flush fitment with stock ride height). You could get away with 265 tires, but I have not tried them.