20" runflat to 20" non runflat opinions
Thread Starter
Senior Member
Joined: Jan 2019
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From: Palm Beach, Fl
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
I don't think they have different calipers. But they do have different rotors. It is code U28. That gets you 360mm rear rotors. Standard is 340mm. I believe the sport package comes with the U28 code for 360MM rear rotors? But personally I can realize this would mean a different attachment point for the caliper to clear the larger rotor. This could create a clearance issue in the front but not rear?? But 2 members have stated they had issues with 18" rims on a sport package. I don't see 2 different part#'s for calipers just rear rotors.
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From: Corona Del Mar, CA
2019 SL450, 2019 E450 Luxury Trim Wagon, 2024 BMW I7 xDrive60
I don't think they have different calipers. But they do have different rotors. It is code U28. That gets you 360mm rear rotors. Standard is 340mm. I believe the sport package comes with the U28 code for 360MM rear rotors? But personally I can realize this would mean a different attachment point for the caliper to clear the larger rotor. This could create a clearance issue in the front but not rear?? But 2 members have stated they had issues with 18" rims on a sport package. I don't see 2 different part#'s for calipers just rear rotors.
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From: Tennessee
2015 MB S550 & 2020 MB GLS 450
I don't think they have different calipers. But they do have different rotors. It is code U28. That gets you 360mm rear rotors. Standard is 340mm. I believe the sport package comes with the U28 code for 360MM rear rotors? But personally I can realize this would mean a different attachment point for the caliper to clear the larger rotor. This could create a clearance issue in the front but not rear?? But 2 members have stated they had issues with 18" rims on a sport package. I don't see 2 different part#'s for calipers just rear rotors.
Thread Starter
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Joined: Jan 2019
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From: Palm Beach, Fl
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
Just as more info, if you are speaking about the codes on the DataMB data sheet from a VIN lookup, I don't have a U28 code. On my 15 S550 with Sport Package and AMG 20" wheel option, the data sheet shows Code 769 AMG 20" Spoked Wheels with Mixed Tires; and Code 772 AMG Styling Package-Front Spoiler, Side Skirt. The only brake related codes are related to the braking features of Distronic Plus.
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From: Corona Del Mar, CA
2019 SL450, 2019 E450 Luxury Trim Wagon, 2024 BMW I7 xDrive60
Thanks. I do have Distronic also. The AMG styling has nothing to do with brakes, it is code 321-sport package and lists nothing about brakes. BUT there are 2 different rear rotors for this car. Base and sport have the same calipers but some have said 18" rims do not fit on the sport package cars???
Thread Starter
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Joined: Jan 2019
Posts: 497
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From: Palm Beach, Fl
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
Of course it would be the front. Your getting confused with that I said there was no difference in calipers and noted there are 2 rotors for the rear. You could probably put a 16" rim on the rear. That is not the issue I am sure. 18" rims are not offered on any model but the base and maybe there is a reason? As 2 other have said they don't work on the sport package. I don't know whats different. But for those of us considering more sidewall with the sport package it appears 19" is as low as we can go. I too looked at the exact description on my sticker and online for the Sport package and it is clearly cosmetic including rims, pedals, side skirts, front and rear bumpers.
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From: SF Bay Area
20 SL450, 23 EQS 580, 13 Ferrari F12, 12 Cayenne S, 22 Turbo S
I had 18" stock rims with Pirelli RF on my 2014 S550 and just switched to OEM 20" AMG wheels and non RF PS A/S3+. Ride is fine, just as smooth as the 18" RFs.
Thread Starter
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Joined: Jan 2019
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From: Palm Beach, Fl
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
Update:
Going on a road trip up north and did a thorough inspection after an oil change. Found a corded, damaged right rear tire! Leaving in less than a week no time for the decided 19" rims, new TPMS and mounting Michelins. I reluctantly and immediately ordered and installed Michelin PSS AS3+. This wasn't the plan but had to be safe for the road trip. Well........I am very impressed with the change. I knew the GY runcraps were bad but this is a huge difference. Changed the whole ride of the car. Running 36 psi presently. Compliant and comfortable. Takes bumps much nicer. Not so harsh as before. Its riding a lot closer to my old W221 w/ 19" rims and Michelins. Driving in the garage on GY runcraps and riding out on 20" Michelins is a very big upgrade in comfort. Obviously I just installed 4 of them so I will be on these for a while. For those in any pothole region I can only imagine more protection on 19" and probably comfort. But in Fla the Michelin AS3 on 20's is pretty nice.
Going on a road trip up north and did a thorough inspection after an oil change. Found a corded, damaged right rear tire! Leaving in less than a week no time for the decided 19" rims, new TPMS and mounting Michelins. I reluctantly and immediately ordered and installed Michelin PSS AS3+. This wasn't the plan but had to be safe for the road trip. Well........I am very impressed with the change. I knew the GY runcraps were bad but this is a huge difference. Changed the whole ride of the car. Running 36 psi presently. Compliant and comfortable. Takes bumps much nicer. Not so harsh as before. Its riding a lot closer to my old W221 w/ 19" rims and Michelins. Driving in the garage on GY runcraps and riding out on 20" Michelins is a very big upgrade in comfort. Obviously I just installed 4 of them so I will be on these for a while. For those in any pothole region I can only imagine more protection on 19" and probably comfort. But in Fla the Michelin AS3 on 20's is pretty nice.
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Thread Starter
Senior Member
Joined: Jan 2019
Posts: 497
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From: Palm Beach, Fl
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
Yep! The ride was so harsh with the run craps that I felt the 19" would be the best bet. I am pleasantly surprised at how much of a difference the Non run flat Michelin is in a 20". Looking forward to our trip now.
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From: Texas
63 Falcon vert
Thanks.
