02/18/2021 Update: Answer to a question nobody asked?
I had given up. My search for 19's, square fitment, custom fitment, one off forged wheels, etc. was going nowhere. I thought I was going to be happy once the wifey gave the green light to just have a custom set of BC Forged made in spec offsets but even that was an exercise in frustration when looking for tires, again. So I gave in. I was resigned to buying tires one section width up from the factory 20" and calling it a day with a spacer up front to fix the goofy stance. Then, while looking one more time at eBay for OEM GLC wheels I came across a listing for 2021 AMG GT 43 wheels. WHOA there! I had to check my spreadsheet twice to be sure but lo and behold, these wheels had within mm's of the exact same spec for offset that the custom set of wheels I was looking to have made by BC had! Two catches though: 1st - they were 19. Would they clear the brakes? 2nd - they have tires, but they're summer HP's. So I got to work trying to find the specifications on the caliper and rotor size for the GT43. Turns out they are the same. Tires? Screw it - at this point I don't care, these wheels had tires on them, being take offs, and the selling price with shipping was under 3k. I pulled the trigger. * Side note - can't say enough good things about the seller. Luxury Wheel Collection out in CA. I paid for the wheels last Friday morning, had tracking information that afternoon and the wheels arrived on my doorstep in MD on Wed. If you're looking for quality like new take offs of OEM Mercedes wheels, check them out.
Anyway, so my lowering module arrived from Belarus on Tuesday, the wheels on Wed. I wasted no time in getting the car up in the air, wheels swapped out, lowering module installed and adjusted. I went down the street to air them up to spec, hit the car wash for a quick high pressure rinse to get the road gunk off and snapped a few pics. To say I'm happy with the results would be an understatement.
Final Specifications:
An important note - when agonizing over tire sizes and options one thing I wanted to keep in mind was that I really did not want to change the ratio of diameter front to rear significantly over the OEM spec. This would/could have an adverse effect on the not just speedometer readings but also the differentials and how the torque management split works correctly. I trust the OEM engineers that the car was designed around specific parameters as far as these data points were concerned. Across the range, 300, 43 & 63 the diameter difference remained the same or equal, regardless of 19", 20 or 21" set ups. So this set up ended up as follows:
OEM Front: 2317mm dia - rev per mile=695
OEM Rear: 2312mm dia - rev per mile=696
AMG GT Front: 2237mm dia - rev per mile=719
AMG GT Rear: 2232mm dia - rev per mile=721 - close enough that I'll take a 1mm difference.
Front: 19x9.5 et 22 w/ 255/45/19 Pirelli P Zero PZ4 - weight savings over OEM 20" 9lbs as measured on each corner
Rear: 19x11 et 18 w/ 285/40/19 Pirelli P Zero PZ4 - weight savings over OEM 20" 6.8lbs as measured on each corner
Lowering module (as of right now, still lots of playing left to do to dial it in - driven in Sport + = no rubbing, no scrubbing, no crabbing) - Front - 30, Rear - 35 *I prefer the rake vs. slammed stance, just my personal preference

I'm seriously contemplating removing the flared rear arches and replacing with the 2021 GLC43 flat arches. I think the flush fitment will look best when it matches front and rear. As it stands, were I to get the rear to match the front I'd have to add a spacer to the rear and I just don't want to do that if I can avoid it. They sit so perfect right now and the scrub radius just adds + with the spacers.


Thanks for reading, thanks to all that contributed elsewhere on the forum. I did a LOT of reading and combing through threads to settle on this. I love how it turned out. I honestly couldn't be happier.
The single biggest takeaway? Yes, AMG GT wheels not only fit our x253 cars, I opine they actually have a better fitment than the OEM spec. Lastly, this thing truly looks, acts and performs like a sports wagon now. More quiet than stock, more comfortable, better grip, better handling. BEST stance. Winning.
To Be Continued....

Start/Original Thread:
*Disclaimer - I have searched. And searched. And searched some more. How did I get here? It started about 1 week into ownership. It appears that the dealer when prepping the car for CPO replaced a single tire in the rear. Drivers side tire looks to be about 60-70% tread wear while the passenger rear tire is new. On smooth roads the new tire has noticeable thrumming sound. They ride stiff as rocks as well. I want these Goodyear run flats off this thing right meow.
So I start looking for new tires. Read all the searched threads about difficulty in finding OEM sizes, having to buy front/rear tires from different sources, etc. That sucks a bit.
So then I start thinking about the benefits of having a bit more sidewall for comfort. So maybe 19's would be a good option?
Searched all the threads looking for 19's, which apparently are a popular option for some of y'all for winter set ups. Good deal. But I'm looking for year round set ups.
So then I start thinking about square vs. staggered set ups. PRO - ability to rotate tires, cost. CONS - looks, will have to run spacer in rear at least to get proper fit/look.
Pro's outweigh the cons for me on this one so I start searching some more. Size and ET issues have pretty much pointed me back to 20's.
So, I settle on 20's squared. I think I'm close. I've spent more time staring at this website and inputting various tire sizes, wheel sizes etc that my wife firmly believes I'm slowly going crazy. https://www.wheel-size.com/calc/?whe...cl=30mm&sr=0mm
I'm getting close. I think. I'm fairly confident I can achieve a clean look w/ a rear spacer. No issue there. I'm confident I'll be improving performance by going 20x9 square, allowing for more contact patch on the front wheels. Before I go down this road, is there any chance anyone out there has experience with a square set up on these things? Pros? Cons? Should I just shut up and replace the tires alone? I'm going crazy...
PS - Forged wheels are out of the budget. If I want a new bike this year (and I do) 6k is going to that instead. OEM+ was my first choice, then I saw how much OEM AMG wheels trade for and, yep, NOPE. Aftermarket has too much available to make that be a viable option.
Open to suggestions, experience, wisdom, etc. Jeers and giggles are perfectly appropriate, especially if you've been here already.
Last but not least - pic for clicks. And I promise I'll detail thoroughly with GOOD photos whatever the outcome of this hotmess express ends up in. Help?

 

50 Views. No replies.

Everyones either waiting and laughing, OR, grabbing popcorn waiting for the comments....

Here's what I'm really close to pulling the trigger on;

20x9 ET 20 TSW Ascari - Standard Fit upfront, +10mm spacer rear.
Toyo Proxes Sport A/S - Ultra HP All Season 275-40-20
Thoughts?

 

Your post was a long read, hence why you haven't had any replies I imagine. However, I am in the same boat as you. I HATE the Goodyear run-flats on my 2020 AMG 43 with 20" rims. Like you I have spent countless hours looking for something to replace them with, but there isn't anything in an all-season tire. I haven't looked at replacing the wheels yet, nor whether it's okay to ditch the staggered setup and go with four of the same wheel (might throw off the cars sensors I'm told by a Les Schwab guy).

So although I don't have any advice to offer, I am wishing you luck and hoping you do come back to share your results - I'll be anxiously waiting!

 

Since you're looking for replies and this is clearly an opinion seeking thread, here goes: You're replacing a forged Mercedes wheel with a cast TSW wheel, not to mention it's in a fake 3-piece design.. You're clearly going for looks and not performance; TSW wheels are known to be a budget wheel. There are better A/S tires than Toyo Proxies. What are you trying to achieve and what is your budget?

Edit: Oh and 19"s are way too small for a performance SUV, it will look off.

 

Truth. I tried to be as detailed as possible. Most of my thread searches turned up half hearted due to lack of detail in post information so if this ever gets referenced in the future, I wanted it to hold up ;-) Truth be told, I've spent more time looking for a solution to this dilemma than any other wheel/tire combo I've run on a car in my life. Have discovered quite a bit in the past few days though. For starters, the staggered vs. square issue is a moot point. The standard GLC comes with a square set up and staggered is simply an option. I know from post searches that many folks use square fit for their winter set ups with zero issues. I was doing some digging around on the configurator for the GLC on MB site and when compared across the 300, 43 and 63 It's literally 1 + 1 + 2 up in size (square, staggered with larger rear, staggered with larger front and rear) so I know I can get the aesthetic I'm looking for with a 63 sized front wheel. Tire options are much better in that size range squared. That's the direction I'm going in and still looking.





That's fair. Also to be fair I was looking for other owners experience going down this rabbit hole, not opinions. I also acknowledge I put it out there for comment so I get what I get, flame suit in hand. As for the wheel in question, I'm well aware that wheel is not a true multipiece design. I'm also well aware there are better tires than the Proxes. That wasn't really the point. Neither are what I'm going to execute either way. The engineers at TSW were able to run some CAD numbers and the spokes won't clear the calipers anyway.

Budget isn't really the issue but I'm trying to be conscious of it at the same time. I've run BBS LM's (yes, real ones) on one of my previous GTI's so higher end performance wheels are something I have experience with. To say that the stance of the finished product doesn't matter would be a lie, as most people would agree. The TSW was a wheel that in my first days of searching for the right combination of offset, size, width and tire ranges looked like it would work well for a reasonable price. Regardless, on to the next, still looking. As to your opinion on the 19's, I say rubbish. A proper 19 fitment with a meaty sidewall on a gently lowered GLC will look spot on. Some people think black wheels look good on cars and I don't agree with that either so there you go. Not here to argue opinions, but thanks for adding yours to the mix

 

Well, this escalated quickly. After 8 days and countless hours digging and digging and digging and phone calls and quotes and...and....and.....I get it. The conclusion I have finally come to? The idea of doing a performance square set up is NOT crazy. The idea of finding an off the shelf wheel to accomplish this with the right stance? Crazy. The closest I could come was HRE's or BBS but both were still compromises in one way or another. Once you go down the rabbit hole you can't go back and in order to get the "just right" fit I'm going to have to go custom. If I'm going to go custom, well, I might as well stay staggered and just do the d@mn thing. So, weighing finally options and builds for set of BC Forged. The GLC that put me over the edge? This monster. I don't know who the owner is, or if they are on here (if you know them, and they are, point them here please) but GOOD LORD. This is perfection. Or damn near close to it - in my opinion of course. Wheels are exceptionally subjective to ones personal taste but damn if this isn't SPOT on. I don't plan to go quite as aggressive in my fitment (especially with a 43 vs. a 63) but very close to this. When I finally pull the trigger on the final set up I'll post here. I'll probably put up a lot of my other research too and how/why I finally ended up with a custom forged set up. BTW - one of the comments up above is still aggravating me and I want to clarify, in case anyone comes across this in the future and wants factual information; the only OEM AMG wheels that are truly forged are the cross spoke wheels, as designated in the OEM parts bin as Cross Spoke Forged AMG wheels. The rest are cast. And TSW wheels are not bargain or budget wheels. They pass the same JLW and TUV certifications as the OEM wheels. ASA, MSW, etc, those are budget wheels. But whatever. Eye Candy: *pics are not mine
SPECS: Front 21x10 (ET Unknown ) 275/35/21 - Rear 21x11 (ET Unknown ) 325/30/21

 

I feel your pain....I'm in the same quandry as I type...lol

 

Don't let someone goad you into a more expensive set of wheels.MB forged weigh a fawking TON, you'll save weight and brakes with the lighter wheels, that's a plus. You buy want you want to buy How long are you keeping the car anyway? I do love popcorn though

 

Dude! The struggle is REAL. Over the weekend I did find this site that has been SUPER helpful in assisting with the imagination and various fitments. LOTS of 43's on this site too. I spent more hours than I want to admit in the early hours of both Sat and Sun this past weekend looking at all of these lol.
https://wheelfront.com/aftermarket-w...m-page-52057=1

It's all good! Wheels are more personal, yet just as striking, than a bespoke tailored suit so the decision can be agonizing. I'm making some calls again today to some manufacturers to sort some final details. The real pain is actually tires believe it or not. Just as I thought I had zeroed in on the perfect set up I was dismayed to find that ultra high performance all seasons aren't available in the sizes I need. Sidewall design and tread width can kill an otherwise perfect wheel combo and when I would find a tire I wanted that fit, it would be available in one size for the front but not the rear and visa versa. Pushing me back to sticking to my guns about doing a square set up with a mild spacer in the rear. Still working on it Oh, and as for the duration of ownership? That's the other kicker - I plan to keep them on this one for the next few years before I trade into another 43/63 so these will be a set that will go from this GLC to the next. That's a factor too with final wheel finish! lololololol....self inflicted pain...I've twice been on the brink of saying F it and just replacing the crap GY run flats, sticking a spacer on the front and calling it a day

 

Updated up top. The madness has ended. Sanity has returned. The stormtrooper has her stance dialed in


Big Brother?

Luxury Wheel Collection out of CA. Can't say enough good things about them. Outstanding customer service, super fast shipping, amazing pricing.

2021 AMG GT 43 OEM 19" wheels + tires.

StormTrooper

That rear end though...

GLC 300 arches in the rear will take that shadow cast off the rear haunches and let the tire shoulder show like the front. Let me contemplate...$1200 for OEM front flares or $150 for OEM GLC300 flares....hmmmm. Easy day.

 

Not a bad looking wheel but I personally think the wheel looks a little too small for the vehicle size. just my opinion. I'm sure the ride is infinitely smoother than the 20's or 21's though. Any noticeable variation in speedo compared to the real ground speed?

 

Yup, just a matter of personal preference. I know it's not everyone's cup of tea for sure and I'm in the minority there. In person it honestly transforms to look more like a wagon than the "Crossover" it pretends to be. I was parked next to a friends Audi All Road the other day and it looks magnificent comparatively. As for the speedo, it's exactly 2.1km/h off. In reality, perfect lol. I can set cruise to 65 and know I'm in the safe zone for the boys in blue. It brakes and accelerates better, without question.

 

Yep, I dig the wheel design, but me thinks the total diameter too small for this rig. Seems a bit lowrider-ish, but on a positive, like a weekend track car as well. I think thicker sidewalls would have helped the overall visual, as in 255/50r19 and 285/45r19, but as long as you're happy.