Hello,

I have had my SL 55 w/ the P30 Performance pack for almost 3 years now and still loving her. Recently, I have found SL55's for sale w/ the P30 pack and noticed front brake rotors are not the 390mm composite rotors my car came with. Obviously, these owners have opted to get the less expensive non composite 360mm rotors. I'm happy that the previous owner replaced the fronts with proper Brembo 390mm composite rotors. However; I have also found some for sale that show rear composite rotors installed!

Did the P30 pack have identical braking system from the SL65 AMG which included 360mm composite rotors or not? I have been researching this for a few days and can't find anything to confirm this. I would like to upgrade soon to the composite 360mm rear rotors to have a "proper" set up for my car. I don't want to be "that guy" who doesn't have to correct equipment on my car. From pictures, I can see my car has the identical 4 piston calipers rear calipers grabbing 360mm composite disc on "proper" P30 cars. Plus...they look so bad *** don't they? But to ad to my confusion, I have found 2007 P30 cars with a different looking rear caliper though. So confused.

Can any experts confirm 360mm (Brembo 2304231412 composites from the SL65 (R230) bolt on with no issues to my 4 pot calipers? Can you confirm these are the disc my car came with from the factory? I can see there is a gap of about 10-15mm before the rear disc installed on the car rubs the caliper body. Thanks in advance.

Here is what I have seen on some SL55 P30 cars for sale online.





Here is my current set up with non composite (330mm?) rear disc.




I believe these are the rear rotors I need to get when replacement time comes:



Here is a 2007 P30 car with the same composite rotors but looks like a different 4 pot caliper .

 

The 03-06 SL55's had different front/rear calipers than the 2007/2008 SL55's. The 03-06 had 8 piston front calipers and 4 piston rears and the 07-08 had 6 piston front calipers and 4 piston rears. This is regardless of rotor size. The front rotor size for the standard 2007/2008 SL55 was 360mm and for the P030 it was 390mm. The front caliper & rotors were the only difference in the SL55 P030 braking system package.

The SL55 rear set up was the same from 2003 thru 2008 regardless of standard or P030 package.

The rear rotors (Brembo 2304231412) you are looking at are for a 2005 thru 2008 SL65 and a 2009 on SL65 Black Series. These rear rotors only came on the 65 Series and were not a part of the P030 package on the 2006 SL55 and will not fit your car.

The 330mm rear rotors on your car are correct.

 

Thanks for that clarification. So I have to assume that all the SL 55’s w/p30 I have found online have upgraded to new calipers and rotors from SL65? If you look at the pic I posted, the rear caliper is exactly the same as mine - visually. 😢.

Realoem.com has horrible parts diagrams and makes it hard to see if part #’s match etc. Thanks again for responding.

 

So it is my understanding that all 2003 through 2008 SL55's had the same rear brake set ups regardless of P030 package or not. The non-P030/P030 difference is in the fronts. Also, all calipers were changed in the Model Year 2007/08 for both the non-P030 and P030 brake systems.


Here is a non-P030 rear brake set up on a 2007 SL55. Are you thinking that this rear caliper/rotor has been upgraded from a SL65? It appears to be the same rear set up as in the last picture in your above post. Which is a little different from your 2006 SL55 due to caliper revisions in Model Year 2007/08. I hope this helps.

 

Oh yes, that is what I have figured out thanks to you...that rear caliper is different from my 2006 model of course. If you look at the two pics of the black SL55 - 2006 P/30 I found for sale online, it has composite rotors with the pre 2007 (peanut shaped) rear brake calipers. The same ones on my car! I have found many more but, I have no way of contacting the new owners. I guess the question I should be asking is there a 330mm composite rotor out there for Mercedes or same bolt pattern? That's the only way I can see how these composites work with pre-2007 (Peanut shaped) rear calipers right?

Here are two pics of a 2006 and a 2005 SL65. See how the rear calipers are the "peanut shaped" 4 pots that are also on my car. Is there a way to confirm that the calipers from these two cars are identical to mine? They certainly look identical in every way. (part #'s match?) I'm going to the dealer as a last check to make me stop this quest for composite rotors. I know having bigger diameter rotors at the rear may upset the balance engineered into the SL55's. Thanks again for all the input.


This is a 2005 SL65 with the peanut shaped pre 2007 calipers.

The pictures with just the wheels/brakes showing are from a 2006 SL65 - I have also noticed that all these rotors seemed to have a polished or machined (silver) hats - not black.








And here is the 2007 and up rear caliper being used to grip 340mm non composites for a C55 upgrade.

 

Another angle may be to search for "AMG Compound Braking System" This was a build code 97V on 2007/2008 models in the code 770 package or as part of the P30 package.

Sorry - I don't have build code info on pre-2007 models, but if you find your build sheet and/or original MSRP sheet, the info will be helpful.

I found my build sheet under the carpet in the passengers side footwell and received my MSRP sheet from Mercedes Benz AMG.

If your vehicle came with SL65 brakes, they would be the two piece 360mm rotors (rear). I have searched for two piece rotors for a 2006 SL55 with P30 package and could not find a single two piece rotor. The P30 package on the 2006 SL55 (1st year) was so limited, I bet that no one makes this specific rotor for your car any longer - unless it is a SL65 piece.

Your MB dealer should be able to help with finding the correct composite 2 piece rear rotors for your car - if your car came this way

 

Thanks. I got a call from a buddy who said there is a 2006 SL65 in their service parking lot with a collapsed suspension! I'm going to head over there on my lunch break and take a closer look at the rear brake set up. Then I'll head in to parts to see if they can solve this mystery. I was able to find an online parts business that did show the part #'s for the rear caliper are different but....no surprise no picture of the caliper. Just some vague pencil drawing. Hopefully, I will lay this to rest today.

Here is another 2006 SL65 I found today on a random site with the "peanut caliper" in question. I also attached the caliper for anyone following this thread in case you didn't know what a peanut caliper looks like

 

Mission to dealer was a partial bust yesterday because I didn't have a tape measure! Parts department was swamped. I took pics of the rear caliper and again, from eyeing it...it looks identical in size and shape as my caliper. I stuck my cell phone in there as a size reference. I'm going back today with a tape measure and hopefully parts won't be too busy.

 

Pardon the sidebar, but which model OZ wheels are those? Any issues with potholes/rougher roads?

 

Ok finally verified that the rear calipers on a 2006 SL65 and identical to my 2006 SL55 caliper - dimensionally that is. They are exactly 7” long from the bottom of the “peanut” to the top. They are 12” long overall and 4.5 “ wide. This was done with a not so flexible aluminum tape measure and had some space issues with the OEM wheel so measurements are not 100% accurate.

Parts is looking into it since they couldn’t verify for sure the parts are internally (piston diameter) alike. The composite rotor on the SL65 is more like a 340mm than a 360mm one. Hard to measure mounted to the car. Parts May have both calipers I stock so we can do a side by side comparison. Stay tuned

 

No worries I’m running 19x9 32mm and 19x10.5 30mm offsets. Also running 10mm front and 5mm read H&R spacers to just push the wheels to the fender lips. 295mm rear tire. I can’t recommend OZ Legerras if you live in a city with bad potholes. Our cars are just too heavy IMO to hold up that abuse. I slightly bent one front wheel after impact with a normal size pothole and had to replace it.

However as I stated before, these wheels are only 23lbs-24.3 lbs rear! The reduction in rotating mass compared to OEM 2 piece wheels is significant. The car felt like it gained 20 hp! These sizes are no longer in production. I may go back to OEM so I don’t have to worry about bending wheels again. OZ Legerra Flow forged wheels are amazing value for lightness and designed but can't compete with more expensive mono forged or heavy cast OEM wheels for strength. IMO.

 

Probably the most critical dimension is your existing rotor size, If you have 330 mm rotors, then the rotor diameter will be right at 13". If you have the 360mm rotors, it will be 14.,17". This will tell a lot.

 

Those OZs look incredible. Appreciate the info, thank you.

On the fence here - would love to reduce rotating mass via lighter wheels (and rotors at some point) but I do encounter the occasional rougher road and would be concerned about bending them.

 

M5zealot - Let us know what you find out. I am not the authoritarian of everything SL55 and you have come very close solving this puzzle. I have great interest in your findings. There are so many questions that are hard to come by with the SL55 like this one.

 

I definitely will. I always strive to know as much as possible about not just my car but others. Had to leave town in business and hopefully my parts guy will have some more clarification soon. He actually went out to the SL65 in the service lot and agreed the rear caliper was physically identical to the ones on my car. He was able to find a number in the rotor but was not the actual part #. Stay tuned

 

Is you decide to get aftermarket, make sure they are MONO FORGED - carved out of a solid block of aluminum! The market is flooded with misleading use of the term "forged!" The newest entry are advertised as forged for about $650 per 19" wheel. I won't name the brand but, these wheels have a mono block face only! They leave a little more material behind the face after it is forged then the material behind the finished face is rolled to create the barrels! So technically they can call them forged but the barrels are flow formed (forged) so they are not going to be as strong a a mono forged wheel. Just FYI. Usually a rule of thumb is any forged wheel about $1K is probably a mono block forged wheel. Anything under.......

 

Sorry for long wait. I found out something we already knew. Part numbers for the SL65 are different from the SL55 P30. My parts guy came outside to "eye" the 2006 SL65 in their lot and he came to the same conclusion. They rear calipers are physically identical to my calipers! markings and position of cotter pins for brake pads are also location in the same spots. We can't remove the wheel because this car is sitting in their "junk" lot waiting for insurance company to access it. We tried to measure the rotor but it's really difficult with the wheel on.

His opinion is, the caliper may be the same but because it's being used on a different model, the part #'s are purposely listed to not match.(?) So I guess cross referencing parts is a pain for MBZ? He said Mercedes does that a lot to avoid confusion. LOL He said if that is the case, the caliper on the SL 65 must be mounted differently on the suspension to give clearance to the 360mm rotor. The only way to verify for sure, is to order the parts and physically compare them on the counter. He's going to see if he can get the calipers from their warehouse and get back to me.

To upgrade to the rotors and calipers will cost $3,835.00 at my wholesale cost! Stay tuned

 

The rotor diameter for 360 mm is just over 14" (14.17"). A 330 mm rotor is 12.99" you should be able to discern the difference by eye balling it with a tape. No doubt, the SL65 has a +14" rotor. If you could find another 2006 SL55 with P30 package or you could always check the diameter with the "eye ball method" on yours. I have a feeling that the calipers on your car are original and just the rotors have changed over time. There are places that give lifetime warranties for the MB rotors, such as FCP Euro. Give them a call with your vin # and they will tell you which rotors came with your car.

Thanks for responding. All info is good info!

 

Of course, I would try to get the rotors wholesale if I can verify they will work. We have a company here called Northside and they sell wholesale to local garages. You usually need a resale license and have an account with them to buy parts. However; they accept walk in customers who are not associated to garages and sell wholesale but charge tax. Customer service is horrible but, they do save me $$$$$!

So, dumb question.......if the calipers are the same for the SL65 and my SL55....will a 360mm rotor fit by changing the mounting point of the caliper a few inches rearward? I never paid attention in geometry class.

 

did you managed to find and answer for this?

 

I'll give some answers even though you weren't asking me. The original thread starter may no longer be following this thread. The only difference between the R230 SL55 and SL65 rear calipers are the length of the mounting ears. The SL65 caliper has to be 15mm farther away from the axle center line in order to be used with the larger 360mm rotor as compared to the SL55 rotor of 330mm (note: the 15mm is the radius difference between the two rotors). The 2007-2011 later rear caliper is simply an update and it looks physically different. It is principally functionally the same as the earlier version, used with 360mm rotor (same braking leverage) and the same piston sizes at 28/30mm (clamping force) between the two generations. Updating to the newer rear caliber on the pre-2007 SL65 models is a simple bolt in, but there would not be any noticable difference in the operation. For those looking to upgrade the rear calipers on other models (SL55, E55/E63 (211), CLS55/CLS63 (219)) either rear calipers - the early 2005-2006 or the 2007-2011 SL65, can be used.

Hopefully, for those coming across this in the future, this will provide the answers they are looking for.