When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
When I purchased my 2017 SL-550 CPO in November 2018, it had 2,800 original miles on it. It's now September 2021 and the SL has 11,845 miles. So I'm averaging about 2,500 miles a year. The CPO expired in June 2021. My Mercedes dealer tells me I'm ineligible to purchase any factory MB brand extended warranty but they are offering an extended warranty with a private company - I looked at the terms of the private warranty and lost interest when I got to the part that they do not cover anything related to a removable hardtop. I'm also very reluctant to purchase any extended warranty not issued by the manufacturer.
I'm 74 years old, totally love my SL, and can easily consider this my "last" car. We have other vehicles but just can't imagine ever getting rid of the SL.
So I'm seeking advice on preventive maintenance. I recently replaced the run-flats with Michelin Pilot Super Sports; the ride improvement was instant and amazing. I usually bring the car to MB for routine service at least once a year. Normally it's just an oil change, both batteries were replaced last year, original brakes with plenty of wear still remaining. The only problem I have had is the top occasionally needs to be coached to go down (never a problem going back up). It's one of those pesky intermittent problems that we can never recreate when it's at the dealer. Dealer has looked at it 3 times, never could find anything to fix. The consensus is, it's a faulty relay or proximity switch. The best workaround I have come up with is to manually open the trunk, cycle the luggage cover to open and close, and then the top will go down just fine. Then the top may operate without any problem for 6 months, but eventually, the problem returns.
My biggest potential concern is the ABC system. I love the ABC but have read so many horror stories about very costly repairs. Any suggestion on PM for the ABC would be much appreciated. Should the hydraulic fluid for the ABC be replaced with just 11,845 miles on the car. Are there seals for the ABC system that I should consider replacing now? Or am I opening up the possibility of introducing a problem by simply performing maintenance on an ABC system that is operating perfectly, at this time?
I have never done a formal A or a B service on this car because of the extremely low mileage. The dealer essentially does the A service (3 times since we purchased the car) but does it for @ 70% of the price of the "FULL" A service. I believe the A should be done at 10,000 miles and the B every 20,000 miles. I'm thinking of having the Full B service done this November even though the SL will only have 1/2 of the recommended miles (20,000) at that time. I'm really not concerned about the cost of the service, I just want to do as much PM as possible to try to avoid having a huge problem in the future.
Half my driving is under 30 mph leisurely cruising around our community and half is at 80 mph on interstates. The car is never driven on high-speed twisting roads. So that's it ( for any of you who have had the patience to read this far). I would really appreciate all suggestions for my future maintenance.
I believe the “B” service is basically the “A” plus a cabin filter change and a brake fluid change. I have owned 18 newer vehicles over the years, many for 10 years or more, and have never had brake fluid changed. I have no idea why MB recommends this time frame. Having owned 3 SL’s I do not remember anyone on these forums writing in about brake problems but if it makes you feel better by all means have the “B” service done. I do all my own oil and filter changes but have a good Indy close by if necessary.
MB says the ABC fluid is permanent but on my R230 my fluid had turned brown by 40k miles so I changed it out myself and will do so on my R231 also.
I'm in the same position. My extended CPO warranty will expire in a few months. I have had a couple warranty repairs done at my local dealer, engine/transmission mounts and non operational Air Scarf. However after paying $250 for an A service that is really nothing more than an oil/filter change I found an independent shop that I will be using for future maintenance and repair. I recently had a B service at the Indy for $180. I provided the oil, oil filter, air filters and cabin filter.
I don't have any issues with my top and don't have the ABC so I can't help in these areas. I'm sure others will chime in.
I recently was charged $1460 for class B1 service on my CLA BM (42,000 miles). I think the cost was excessive. What to others think. Comments, suggestions, and other viewpoints welcome.
The OP’s situation is not dissimilar to mine, when I recently purchased an 8 year old SL63 but with only 20k miles. Per the maintenance book, there are several services that are listed at “40,000 miles or 4 years”; for the AMG SLs these include transmission and differential fluid changes at this interval. My car had been fully dealer-maintained but had had routine oil and brake fluid changes and nothing else. I proceeded to have all these services done, via a combination of DIY and at an independent mechanic.
Personally I believe in maintaining cars precisely as their manufacturers recommend, and by interpreting combined miles and time intervals as “whichever comes first”. If a car has lower than average miles, it could be because it was routinely used for short trips, or it could be that it was used only intermittently but for longer trips. The former of these situations is more damaging than the latter, and indeed counts as “severe service”. Not knowing how my SL had been used previously, I opted to assume it had been “severe service”.
Regarding brake fluid, it’s not only Mercedes that has a routine replacement interval, but also Porsche, BMW, and Honda/Acura, in my direct experience. Brake fluid absorbs water and turns corrosive. In the past, Ford had a problem with their steel caliper pistons getting corroded and jammed - they addressed this by going to non-metallic phenolic pistons, but then they had a problem with those pistons getting deformed over time. I do not know if or how they have addressed this in late model Fords. Presumably the other manufacturers have addressed this by specifying a fluid replacement interval. I take the view that they know more about their cars than I do, so I stick to their recommendations.
Regularly changing brake fluid is more critical in extremely high humidity locals - we live in Florida. We owned a GEM golf cart - it's registered as a low-speed vehicle that can be driven on any public road up to 35 MPH. We meticulously followed the recommended service on the GEM but they did not recommend regularly changing brake fluid. Out for a ride, one day and the brake pedal went straight to the floor. When the dealer picked up the GEM for repair he informed me the entire brake system needed to be replaced due to water intrusion in the system.
We're originally from New England and had never experienced the near 24/7 humidity of Florida. Also, had never experienced brake fluid absorbing water into the brakes on any vehicle. The cost of servicing your brake fluid is a pittance when compared to the cost of replacing your entire brake system.
Fortunately, it appears as though the r231’s have been somewhat reliable with “relatively” minor issues.
My car is older than yours, so I’m further along the service cycle. I also work on a couple of others.
Besides the obvious consumable items, and the ABC issues others have touched on.
For me, “preventive” As in easily preventable, potentially high cost repair items I watch for on m278/r231’s :
I keep an eye on the cam sensors as in some M278’s they can weep oil into the wiring harness all the way up to the ECU and O2 sensors. May require engine removal to replace wiring harness 😮
Every oil change I remove the connector and inspect them. There are a few threads on this subject. You can search to see the gory details. It can be ugly 😕
The chain tensioners can be a headache. Chances are since your car’s a 2017 and quiet, you’re good.
The shifter is electronic and prone to contamination/moisture damage. Don’t let the detail guys spray crap in that area! And don’t spill anything in there.
The intercooler/oil lines to the turbo can become brittle/leak after 6 yrs /35k or so miles. They are exposed to a lot of heat. Keep an eye on them.
The charge air temperature sensor can be due for a replacement about that time too.
Needless to say, if you’re a DIY’er, the ability to run Xentry is invaluable to keep an eye on potential issues that can cascade into bigger and more costly repairs. I honestly wouldn’t even consider a shop that can’t fully scan these vehicles.
I typically do the regular brake fluid flushes (with geographical location being a factor also) Once every couple of years max. (for me personally).
MBZ uses DOT 4+ which is still hygroscopic. Corrosion in caliper piston bores can cause pitting leading to piston retraction/leaking issues or master cylinders can also be more prone to internal/external leaks over time. It’s just cheap insurance. If you’ve ever rebuilt calipers, you may have seen the sludge that can build up in there if neglected.
These things are like a vacuum cleaners. They flow a lot of air volume 😀 inspect the air cleaners often!
LOL! Here’s an air cleaner I pulled off recently.
Last edited by crconsulting; Sep 1, 2021 at 08:43 PM.
For those who plan on a Do it yourself ABC fluid change in the future this tool is a must. On the R230 you could unplug the return line to the reservoir but this is different on the R231 and this tool is shear genius. Watch the film on this site for application. In the film the MB has a screw cap on the reservoir but the set up on the R 231 is not the same. https://agatools.com/products/aga-mb-abc-ft
The only problem I have had is the top occasionally needs to be coached to go down (never a problem going back up). It's one of those pesky intermittent problems that we can never recreate when it's at the dealer. Dealer has looked at it 3 times, never could find anything to fix. The consensus is, it's a faulty relay or proximity switch. The best workaround I have come up with is to manually open the trunk, cycle the luggage cover to open and close, and then the top will go down just fine. Then the top may operate without any problem for 6 months, but eventually, the problem returns.
I have helped two friends use the tool on their MB’s with ABC and it works great but their cars have screw on caps on their reservoirs. Have not tried yet on the R231 and have not looked at the cap recently.
My fluid is still light green and I only have 14k miles so far.
MB had it in their shop 3 times. Said they could not duplicate the problem and never mentioned a code to be. On occasions, when I try to put the top down, the message "vario roof operation" pops up but the roof does not move. Sometimes I can hear a mechanical "clunk" from the trunk area but still no movement. It I lift the top-down switch (to open), then press the top-down switch (to close) then lift it a second time, the roof may go down. As I said in my original post, the best way to fix it is to exit the car, manually open the trunk, cycle the luggage cover and close the trunk manually. At that point, the top-down works normally while seated in the car. The top will then function properly for weeks, sometimes a month, but the failure to open problem always eventually returns. It's one of those intermittent things that is so hard to diagnose unless it fails while at the dealership.
As you experienced with your golf cart, regular brake fluid changes are critical--one of the best examples of preventive maintenance that I can think of. The industry standard is every 2 years, but even every year would not be too often in a state like Florida. Most brake fluid starts off as a clear liquid. The more water it absorbs, the yellower it gets, then amber, then dark amber, then brown.
The water content will indeed lead to corrosion in the calipers, with dangerous and expensive consequences. But it also reduces the boiling point of the brake fluid. Your driving sounds fairly relaxed, but descending a long mountain road could still lead to boiling brake fluid--which then turns into a gas, which compresses easily and causes the brake pedal to go to the floor (or partway, with dual-circuit brakes). Not a good situation, obviously.
Regarding the ABC system, my understanding is that the R231 cars (like yours) have a much-improved and more reliable version compared to earlier cars. Fluid changes still sound like a good idea, but longer intervals between changes should be okay--say, every 4 or 5 years?
Regarding the A and B services, I would go by the number of years since the car was new, rather than the 10,000 and 20,000 mile standards. I.e., an A service in every odd-numbered interval since new, and a B service in the even number of years. If it's done at a dealer, try to ensure that they actually do the long list of checks that they're supposed to.
It's a good idea to use a very high quality gasoline, such as Shell's V-Power. It has a ton of cleaning agents that can help keep the fuel system in good shape, including the injectors.
My final piece of advice regarding preventive maintenance is the fun part: Be sure to accelerate hard every so often (after the engine has warmed up fully, e.g., after at least 10 mile of driving). It's not as important as back in the carburetor days, when an "Italian Tune-Up" could perform wonders. But it does allow the accelerator components, airflow sensor, MAF, etc. to operate throughout their range.
Oops, almost forgot: Occasional really hard braking from 60+ mph will also help keep the rotors from corroding. Yes, it will wear the brake pads more quickly, but with relaxed driving at other times, they will still last a long time.
Rick F.
PS: It's good that you have a record of problems with the top operating correctly, while your car was still under warranty. If it fails altogether, or at least in a repeatable way, Mercedes should stand by a repair even though the car is now out of warranty.
As you experienced with your golf cart, regular brake fluid changes are critical--one of the best examples of preventive maintenance that I can think of. The industry standard is every 2 years, but even every year would not be too often in a state like Florida. Most brake fluid starts off as a clear liquid. The more water it absorbs, the yellower it gets, then amber, then dark amber, then brown.
The water content will indeed lead to corrosion in the calipers, with dangerous and expensive consequences. But it also reduces the boiling point of the brake fluid. Your driving sounds fairly relaxed, but descending a long mountain road could still lead to boiling brake fluid--which then turns into a gas, which compresses easily and causes the brake pedal to go to the floor (or partway, with dual-circuit brakes). Not a good situation, obviously.
Regarding the ABC system, my understanding is that the R231 cars (like yours) have a much-improved and more reliable version compared to earlier cars. Fluid changes still sound like a good idea, but longer intervals between changes should be okay--say, every 4 or 5 years?
Regarding the A and B services, I would go by the number of years since the car was new, rather than the 10,000 and 20,000 mile standards. I.e., an A service in every odd-numbered interval since new, and a B service in the even number of years. If it's done at a dealer, try to ensure that they actually do the long list of checks that they're supposed to.
It's a good idea to use a very high quality gasoline, such as Shell's V-Power. It has a ton of cleaning agents that can help keep the fuel system in good shape, including the injectors.
My final piece of advice regarding preventive maintenance is the fun part: Be sure to accelerate hard every so often (after the engine has warmed up fully, e.g., after at least 10 mile of driving). It's not as important as back in the carburetor days, when an "Italian Tune-Up" could perform wonders. But it does allow the accelerator components, airflow sensor, MAF, etc. to operate throughout their range.
Oops, almost forgot: Occasional really hard braking from 60+ mph will also help keep the rotors from corroding. Yes, it will wear the brake pads more quickly, but with relaxed driving at other times, they will still last a long time.
Rick F.
PS: It's good that you have a record of problems with the top operating correctly, while your car was still under warranty. If it fails altogether, or at least in a repeatable way, Mercedes should stand by a repair even though the car is now out of warranty.
Thank you Rick, for that very comprehensive and detailed reply. Much appreciated
One more I forgot.
Maybe obvious to most, but can’t tell you how many people don’t realize there are two coolant tanks/circuits in these cars.
Check your intercooler coolant level once a year. It shouldn’t leak but may have to top it off if it’s never been looked at.
It’s a separate tank UNDER the engine cover. You have to remove the engine cover to see/get to it. 😀
Last edited by crconsulting; Sep 3, 2021 at 06:43 PM.
MB had it in their shop 3 times. Said they could not duplicate the problem and never mentioned a code to me.
The vario roof should store some trouble codes, The dealer should be reading them. It’s possible they didn’t store but the vario roof has quite a few micro switches.
Did they even scan the car? Next time you bring it in, ask them if it triggered any codes?
Here’s one on a car that had intermittent roof issues. It kept triggering codes and had a faulty top module: 2319006905. It has redesign/superseded part#: 2319003608
I cleared it several times but kept coming back. After replacing module, top now works perfectly.
Since the OP states that cycling the luggage cover fixes the problem (temporarily or otherwise), the cause must be related to a sensor or microswitch in the luggage cover mechanism. I have no idea where these sensors/switches are, but it might be worth a shot to find them and clean them.
Since the OP states that cycling the luggage cover fixes the problem (temporarily or otherwise), the cause must be related to a sensor or microswitch in the luggage cover mechanism. I have no idea where these sensors/switches are, but it might be worth a shot to find them and clean them.
Easy place to start, 👍
You would think he would get the trunk partitionopen message on his dash.
But those switches CAN be finicky as others have experienced. https://mbworld.org/forums/sl-class-...partition.html
Easy place to start, 👍
You would think he would get the trunk partitionopen message on his dash.
But those switches CAN be finicky as others have experienced. https://mbworld.org/forums/sl-class-...partition.html
I need to go experiment to see if I get that message. When I was test driving the car, I wanted to fold back the roof and the salesman showed me how to do it. Except nothing happened. So he hopped out of the car, opened the trunk, did something, hopped back in, and the roof worked. He stated that he had gone to check on the luggage partition and sure enough it needed to be closed. Anyway at that moment I do not recall any error messages anywhere.
I need to go experiment to see if I get that message. When I was test driving the car, I wanted to fold back the roof and the salesman showed me how to do it. Except nothing happened. So he hopped out of the car, opened the trunk, did something, hopped back in, and the roof worked. He stated that he had gone to check on the luggage partition and sure enough it needed to be closed. Anyway at that moment I do not recall any error messages anywhere.
That's exactly what is happening to me but it is aggravatingly intermittent. I can go for months with no problem, and then it won't open. Sometimes recycling the top-down/up switch resolves it but the easiest fix is to exit the car, open the trunk, manually cycle the luggage cover closed. It has to be a proximity switch/sensor/relay in the top mechanism but my MB shop has not been able to find the source after 3 visits. The shops biggest problem seems to be they can never duplicate the malfunction when they have it. Once worked on it for 3 days.
Since the OP states that cycling the luggage cover fixes the problem (temporarily or otherwise), the cause must be related to a sensor or microswitch in the luggage cover mechanism. I have no idea where these sensors/switches are, but it might be worth a shot to find them and clean them.
I'm with ram_g. It absolutely sounds like a luggage compartment cover issue...
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
