CLS 450C Oil Consumption
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2015 S-550
CLS 450C Oil Consumption
My 2020 CLS 450C (6 cyl gasoline engine) has 600 miles and the oil is already down by about half a quart. Never had a Mercedes or any other car that burns so much oil. Comments from other CLS 450C owners would be appreciated.
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From: Port St. Lucie, Fl
2026 GLE 450 (Black on Brown Saddle)
My 2019 CLS 450 with 19,600 has consumed about a quart of oil after 5,500 mies and another one after my Service A. The addition of oil is normal since this new inline 6 cylinder engine do run very hot. I would just keep a record to track the interval. My two service advisors and technicians have confirmed these events. 
Last edited by haibieb; Dec 4, 2020 at 03:25 PM.
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2015 S-550
Thank you for reply. 1 qt/5500 miles is still high but not as bad as my CLS. I hope it gets better after break-in. I have owned about 23 cars and can't recall that I have ever added oil between scheduled oil changes. Besides, I don't care for the oil quantity meter on the CLS. Much prefer a dipstick which also allows me to check that oil has been changed by checking the color of the oil. With the oil meter on the CLS the shop could just top up and I have no way of verifying oil change.
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From: North Scottsdale, AZ
'71 Pinto
Request oil consumption test under warranty.
Based on customer’s information, if the oil consumption is less than 0.50 quart/1000 miles or 2000 miles/quart, no further measures are necessary. If oil consumption is greater than 0.50 quart/1000 miles or 2000 miles/quart, perform oil consumption measurement by weight as follows.
1. Check engine for external oil loss; e.g., oil leaks.
2. Pre-condition the engine of the vehicle by completing the break-in process of the engine as follows:
a. Check the oil level and correct level if necessary.
b. Drive the vehicle for 1 hour under high load and high engine speed (between 4,000 and 6,000 rpm) appropriate on the local conditions and circumstances.
c. Vary the engine speeds during the road test. Note: If possible perform this test on interstate type roads where speeds of 55 – 65 mph can be obtained and use the appropriate transmission gears to maintain engine speed of 4000 to 6000 rpm.
Based on customer’s information, if the oil consumption is less than 0.50 quart/1000 miles or 2000 miles/quart, no further measures are necessary. If oil consumption is greater than 0.50 quart/1000 miles or 2000 miles/quart, perform oil consumption measurement by weight as follows.
1. Check engine for external oil loss; e.g., oil leaks.
2. Pre-condition the engine of the vehicle by completing the break-in process of the engine as follows:
a. Check the oil level and correct level if necessary.
b. Drive the vehicle for 1 hour under high load and high engine speed (between 4,000 and 6,000 rpm) appropriate on the local conditions and circumstances.
c. Vary the engine speeds during the road test. Note: If possible perform this test on interstate type roads where speeds of 55 – 65 mph can be obtained and use the appropriate transmission gears to maintain engine speed of 4000 to 6000 rpm.
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2015 S-550
konigstiger - thank you for reply. I'm going to keep an eye on this. I have also noticed quite inconsistent readings from the oil measurement system. Most of the time it shows "more than 1/2 quart down" but sometimes like this morning, before I started the engine, it showed less than 1/5 quart down, assuming that the difference between MIN and MAX is 1 quart. The car has 650 miles.
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e350 2014 CLS450 2021
no dipstick on 2021 CLS450
Newbie here. Question. I just purchased a 2021 CLS450. There is no dipstick on the engine. I read that MB has gotten rid of it on newer cars (I have a 2014 e350 and the car does have a dipstick). Are you folks checking the oil level on the front main panel? if yes then do you think it's accurate?
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From: Port St. Lucie, Fl
2026 GLE 450 (Black on Brown Saddle)
Newbie here. Question. I just purchased a 2021 CLS450. There is no dipstick on the engine. I read that MB has gotten rid of it on newer cars (I have a 2014 e350 and the car does have a dipstick). Are you folks checking the oil level on the front main panel? if yes then do you think it's accurate?
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2015 S-550
I disagree. The readings are very inconsistent. This is the first time I carry a can of oil in the trunk. If the system fails there is no back-up. Really dumb. Never heard of a dipstick failure.
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e350 2014 CLS450 2021
Thank you. I read the manual last night and they also say to check via command system. I personally liked the old dipstick method better as I am old school. But it is what it is. Also, these turbo engines get very hot. I assume the car will burn more oil. Only time will tell.
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2015 S-550
My 4 previous cars had turbo engines, incl a twin turbo V-8. I did not notice excessive oil consumption and never had to add oil between tune-ups. The engine will not run 'hot' if the cooling system has been designed properly. The oil quantity indication on my 2020 CLS450C is about as inconsistent as it can be. Sometimes it shows 'max' sometimes 'min', so what is it? The MB dealer says 'it is normal'. IMO it is a POS.
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Joined: Jul 2018
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From: Port St. Lucie, Fl
2026 GLE 450 (Black on Brown Saddle)
(Reply to ELMALO) If that is your case, take your car to the dealer and have them diagnose the inconsistent readings. This way you have a record on file. That's what I did when I noticed the first "warning" of adding a quart of oil to my CLS. The dealership found no issues and added a quart of oil. So far, I have had no issues with added oil warning or notices.
Last edited by haibieb; Apr 14, 2021 at 10:47 AM.
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From: Europe
2019 CLS 53 AMG
Never look at the digital oil measure sensor... It's not reliable at all. I have BMW also and there you can force the measurement in Mercedes you can't.
I did some tests. After 6000km it was showing 1/3 on the digital display. I added 30ml (almost none) to force the measurement - it turned out to be max!!!!!! Don't ride on 0W20 oil too (this car shouldn't be driven on this pathetic oil - it was just an idea for homologation)... If you put the car on any hill for more than 15min you will see less oil, some times "recheck" comes in 1 day, sometimes in 2 weeks, but if you want to FORCE the recheck you need to add some oil. I spent tons of time trying to figure out how this oil measurement works and it is not accurate at all.
In general the more often you go uphill, downhill the more crazy measurement you'll have. Drive 5000km than add just a cup of oil, run on flat roads let the measurement show "Performing measurement" or something like that (adding oil will force it) and after 30min you'll see REAL reliable amount of oil. Everytime I need to go to replace oil I'm adding before it a cup of fresh oil to force the recheck to see "real" oil burn driving on flat roads until measurement will be done. So far it is ZERO.
It made me nuts too.
BTW : If you drive this car on 0W20, well you deserve to get burn lots of oil.... I'm using Racing 5W40 oil with MB 229.51, I don't burn even 100ml per 7000km in reality, but it doesn't mean I don't have big jumps on this weird oil level sensor.
Until the car will shout you "Add 1L (or quart) of oil" you should not react at all.
For CLS450 - here you got all engine oil specs approved :
https://bevo.mercedes-benz.com/bevol...carspecid=6737
I did some tests. After 6000km it was showing 1/3 on the digital display. I added 30ml (almost none) to force the measurement - it turned out to be max!!!!!! Don't ride on 0W20 oil too (this car shouldn't be driven on this pathetic oil - it was just an idea for homologation)... If you put the car on any hill for more than 15min you will see less oil, some times "recheck" comes in 1 day, sometimes in 2 weeks, but if you want to FORCE the recheck you need to add some oil. I spent tons of time trying to figure out how this oil measurement works and it is not accurate at all.
In general the more often you go uphill, downhill the more crazy measurement you'll have. Drive 5000km than add just a cup of oil, run on flat roads let the measurement show "Performing measurement" or something like that (adding oil will force it) and after 30min you'll see REAL reliable amount of oil. Everytime I need to go to replace oil I'm adding before it a cup of fresh oil to force the recheck to see "real" oil burn driving on flat roads until measurement will be done. So far it is ZERO.
It made me nuts too.
BTW : If you drive this car on 0W20, well you deserve to get burn lots of oil.... I'm using Racing 5W40 oil with MB 229.51, I don't burn even 100ml per 7000km in reality, but it doesn't mean I don't have big jumps on this weird oil level sensor.
Until the car will shout you "Add 1L (or quart) of oil" you should not react at all.
For CLS450 - here you got all engine oil specs approved :
https://bevo.mercedes-benz.com/bevol...carspecid=6737
Last edited by F1le; Jul 22, 2021 at 06:08 PM.
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