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I bought a 2020 GT R Pro with 6500 miles. The Mercedes dealership did a oil change and complete service before i took delivery of it. As soon as I drove off the lot the warning message reduce oil level came on. I brought it right back and they evacuated about a quart out of it to 6.1 q. Driving home the light came on again. Brought it back and they replaced the oil level sensor and did a new oil change. The oil level shows 5.1 q and my dipstick shows the minimum level reading. According to the owners manual I am 2 q low now. The dealership is telling me this is normal because when I drive the car like it is suppose to be driven the oil level will come up with expansion. If this is true how come the manual does not address this. I have never heard of this before. The car is suppose to have 7.4 q. why when I check manually or in diagnostic mode cannot I not get the correct reading. How much is sitting in lines or bottom of sump.
unfortunately the oil sensor is overly sensitive and I've experienced the same thing after an oil change. Regarding your question about dip stick readings the engine has a dry sump system which holds oil in a tank as opposed to a traditional oil pan. So yes the dealer is correct. The correct way to check level using the dip stick is to make sure car is completely warmed up to normal operating temp. On flat surface shut the car off, wait 30 seconds, then check the oil. If checking on a cold car oil level will read low. Hope this helps and congrats on the PRO!! Love mine.
congratulations on the PRO! you will love it, a great car to own
Like others said, the oil level sensor is extremely sensitive in these cars, sometimes that warning message come up after I tracked the car for a day, you'd think there should be oil burnt instead of excessive..
I just ignore it, the dry sump system has a lot of tolerance, and I usually just measure when oil is warm (200F+), and use the stick to determine.
This engine does need 7L or 7.4QTS. If you know you're only 5.1 you want to correct the oil level; however, 5.1QTS would definitely set a warning message.
The way the oil is changed in this platform is critical to follow the procedure. You were at an MB dealer and I guess we should assume they know the procedure. If they did not follow it, likely it will result in an overfill which you first reported. Here is the process. It includes some upfront steps and a timing step. I suspect the 3min part was exceeded.
If these steps are not followed, especially the 100*C engine oil temp, 30 sec or more idling in neutral, and the 3 min drain time, then likely as much as a quart of oil stays trapped in the cooler and lines behind a thermostat that closes. Maybe the MB dealer didn't follow these steps.
On checking the oil level with the stick, it too has a critical time window in which you have to check the level properly. For similar reasons as the drain process, the oil level can change in the tank giving an incorrect reading if you wait too long, and if the oil temp isn't up to op temps and idling for 30 sec in neutral in mode C.
Suggest you consider following the steps right above and get an accurate reading on the dipstick, then correct the level.
Indeed they do NOT follow procedure. Every time. I am going to do it myself as syphoning out the extra liter takes the same amount of time.
Funny, that when I changed my oil, I took a drive and it took about 45 mins to get the oil temp up to 100*C...and I live in Phoenix where the air temp is 100*F. It strikes me as hard to believe the dealer is taking in a GTxx and getting the oil temp up to 100*C. If they pulled the car into the bay, started it and let it idle, it'd take half a day idling (if at all) to reach 100*C; or, they're driving it for close to an hour?
So, if they don't get the oil temp up, the tstat to the oil cooler will not open. If they bring it in cold and just dump the oil (Pretty darned sure this is it), there easily will be a QT of oil left in the cooler and lines. Then when they add 7.4 QTS on the fill.....car now probably has 8 1/2 QTS of oil in it.
OR,
They're smart and only put 6 qts of oil on the refill which would be an 81% oil change. Some old oil and some new oil....
This engine does need 7L or 7.4QTS. If you know you're only 5.1 you want to correct the oil level; however, 5.1QTS would definitely set a warning message.
The way the oil is changed in this platform is critical to follow the procedure. You were at an MB dealer and I guess we should assume they know the procedure. If they did not follow it, likely it will result in an overfill which you first reported. Here is the process. It includes some upfront steps and a timing step. I suspect the 3min part was exceeded.
If these steps are not followed, especially the 100*C engine oil temp, 30 sec or more idling in neutral, and the 3 min drain time, then likely as much as a quart of oil stays trapped in the cooler and lines behind a thermostat that closes. Maybe the MB dealer didn't follow these steps.
On checking the oil level with the stick, it too has a critical time window in which you have to check the level properly. For similar reasons as the drain process, the oil level can change in the tank giving an incorrect reading if you wait too long, and if the oil temp isn't up to op temps and idling for 30 sec in neutral in mode C.
Suggest you consider following the steps right above and get an accurate reading on the dipstick, then correct the level.
This is what they ended up doing on my car. The reading is 5.1 in diagnostic mode and minimum on dipstick. They actually replaced the oil level sensor. Not anywhere on my car can I get a correct oil level reading. I followed the steps as mentioned to check the dip stick level. See below as this copied and pasted from my repair invoice.
CUSTOMER STATES THAT THERE IS A MESSAGE ON THE DASHBOARD "HIGH
OIL LEVEL" PLEASE CHECK AND ADVISE.
184110 W67 REPLACE SENSOR FOR N/Cp
OIL LEVEL INDICATOR
Tech(s): 5346
091-905-71-01 1 FILL LEVEL SENSOR N/C
001-997-72-41 1 SEAL RING N/C
000-989-79-02-19-BIFU 6 229.5 5W-40 N/C
Pts: 0.00 Lbr: 0.00 Other: 0.00 Total Line A: 0.00
Story: 6888 HIGH OIL LEVEL ON IN DASH W- CONFIRMED HIGH OIL LIGHT
ON IN DASH. AFTER VERIFYING, ( CAME BACK 3 TIMES AFTER
VERIFYING THE LEVEL BEING CORRECT) LEVEL WAS CORRECT PER WIS
INSTRUCTIONS, NECESSARY TO COMPLETE COMPLETE OIL DRAIN AND
REPLACE OIL LEVEL SENSOR DUE TO FAULTY INTERMITTENT SIGNALS.
REMOVED OIL FILTER AND HOUSING. DRAINED OIL PAN. DRAINED
MAIN RESERVOIR. REMOVED SUBFRAME BRACE TO ACCESS OIL
RESERVOIR//NECESSARY TO R&R LEFT FRONT WHEEL, R&R LEFT FRONT
FENDER LINER, R&R OIL SUMP RESERVOIR. REPLACED OIL LEVEL
SENSOR. FILLED WITH 6.8 QUARTS OF OIL, CHECKED OIL FLOW IN
WORKSHOP MENU IN THE DASH. FOLLOWING WIS GUIDELINES. SHOWED
4.8L MAX FLOW. ADDED REMAINDER OF OIL FOR 7.4 QUARTS.
CHECKED WORKSHOP MENU AGAIN. SHOWED MAXIMUM OIL FLOW OF 5.4L
ON SHOP FOREMAN'S TEST DRIVE. RECOMMENDED TESTING AGAIN
AFTER VEHICLE SETS OVERNIGHT TO QUALITY CONTROL REPAIR;
CUSTOMER DECLINED SECONDARY TEST TO CONFIRM REPAIRS.
05-26-2021, 10:08 AM
