AMG Brake swap success! (w221)
if you then upgrade the calipers will it not lock up more easily? and whilst the 20" give more clearance the discs look tiny?
https://www.willtheyfit.com/index.ph...8-5&offset2=43
I was sharing a great link to help visualise and measure different wheels, tyres and any impact on the speedo
I wanted to understand the tyre diameter you had, as the wheel to arch clearance isn't stock. (Now I know the wheels are almost bang on std, I know its coming from reduced ride height of about an inch)
With more clearance on the bigger wheels the discs look smaller than std.
There were three brake sizes/options from birth in 2005:
a) std,
b) sports with bigger fronts and vented rears (I believe these came as std on the long wheel base cars)
c) AMG giants
My interest is in your thoughts on the ride and handling changes with different sized wheels?
Here's mine and I find it hard to believe the impact could be so significant on two cars both using the std parts (and with 95% in the wrong direction)
I had two European GM made cars, very similar to a https://www.edmunds.com/chevrolet/lumina/1998/review/ the first had 15" wheels and its ride and handling was fantastic (a bit woolly but the mix was very good) They face lifted it with updated suspension bushing and 16" wheels after about 4 years. I expected a huge leap in ability... I had one of these too and the whole car was far worse.... its handling went brittle and nasty and you had to drive it much slower and was far less fun. (EDIT: Came to me over night. It had 15" on the first one, then 16" on the facelift and the last run out ones were blinged up with 17")
And now I just had the same on my S class. It came as Std with 17" wheels running 235/55/17 99W on 8" ET43 wheels and they look silly (far too small) its handling was fairly average, clearly its a lot of car and weight to throw about. So the intention was to upgrade one day to the 18" option alloys and keep the narrow 17" on winter tyres. When I put winter tyres on the car (with the 17" wheel I kept to the narrower 235 width for snow) I found the car squirmed about the road a bit more and the rear wandered slightly on hard acceleration and the grip seemed to drop away quite a lot from the summer originals (none of that surprising - but mentioning for a reason) but I got used to it and it wasn't terrible.
In the end the 18" wheels sat in the garage as I was doing so little miles I didn't bother swapping and kept the winter tyres, they were surprisingly adequate and stayed on the car for 2 years. Then they wore out so I got original fitment (for our market) MO Dunlop's to go with the option wheels.
So its now on "Merc Original" Dunlop's with 255/45/18 99Y on Merc Original 8.5" ET43 option wheels. And the car is transformed.... It is now brittle and awkward on nasty UK roads, the ride is now quite a lot worse and far below acceptable. Its about 20% rougher than the 17" were when using sport, when actually using comfort. But perhaps the most astonishing change is the total lack of grip in nearly every circumstance.
From worn out budget winter tyres that were safe and secure (but worse than the original 17" Michelin summer tyres) to larger and wider, MO wheels and tyres, in the dry it slides about and the car no longer copes with our nasty roads. And now its colder its caution all the way, with big ABS intervention, big wild slides and drifts all the time. And generally being out of its depth.
There were some tiny upsides but none worth the money. Under full on abuse out of 40mph corners the car is better balanced.... you can push the fronts harder in certain dry conditions, but under braking they are pathetic, with no grip at all (warm and dry) and outright horrendous in the cold and damp.
Not sure the word cattle grid crosses the pond, but in the UK. To keep cows in fields and not wandering down the road, we have metal grids on some country roads they are the full width of the two lanes and then about 8 foot in length. Fit two at each end and the cows never cross them. Usually you fit them on the straight bits but there's one near me that's on a high speed corner. When you were young and nothing was on the road you can do it at 80mph in the dry but you have to think about it. And in the rain you'd die trying that. So without others on the road, you can straighten things out, and stick to about 50mph in cold / damp conditions and expect a small wriggle from both ends. I regularly do it on cars and bikes in all weathers and temperatures and having used for 30 plus years, I know what to do and how it behaves. But after I went to these 18" wheels on my S class at as little as 25 mph it tries to slide off the road in dangerously exciting ways I've never come across before. On the winters it didn't even wriggle like other cars do.
Overall its like the difference riding a motorbike in the dry and then in the rain. One you get on with it nothing happens, but weirdly the change to 18" is like a bike in the rain.... you have to go more gently and don't enjoy it.
Last edited by BOTUS; Dec 14, 2020 at 08:13 AM.
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I am having an issue hopefully someone can help me with. I have a 2007 Mercedes s550. I was trying to find out if any of the other models of brakes would fit my car. My installer conducted some research and found that the E55AMG front and rear calipers will fit the 2007 s550 but you must use E55 AMG front rotors and SL55AMG rear rotors due to the parking brake setup. No problem with setup on front but the rear SL55AMG rotor will not align/center with E55AMG rear caliper. But it will align/center just fine when its off the car. Pictures attached. The rotor is about 1/4 inch forward of the caliper center line. Does anyone know if something else must be done for this to work. Possibly an adapter needed for the rear caliper? Any assistance would be great.
E55 AMG rear caliper and SL55 AMG rotor will not aligned/center when trying to install on the car
E55 AMG rear caliper and SL55 AMG rotor aligned off the car
SL 55 AMG rotors
E55AMGrotorandE55AMGcaliper
E55AMGcalipersfrontandrear
Last edited by bayou340; May 2, 2025 at 12:33 AM.







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