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oil level check

2K views 5 replies 4 participants last post by  drivbiwire 
#1 ·
Hi all. Wondering about the accuracy and latitude of the oil check mechanism. Just did and oil change. Level check prior to change read 'oil level OK'. Siphoned off 8.25 quarts (guess who got a mityvac for Christmas). started putting oil in and checking level after I had put 5 in, then kept checking regularly. I got a 'oil level OK' at the 7 quart point. This, of course, is 1.25 quarts less than what came out but oil level sensor was happy with both. It did indicate to add 2 liters more when I checked it earlier, so the float, or whatever the engine uses to determine level, does work.
So, did I have too much before, not enough now, or does this engine have 1.25 latitude on measurement?
BTW, I did not do the filter as it and the oil only had 2K miles on it but I wanted to put a better oil in.
Thanks for any insight.
Larry
 
#2 ·
According to the user manual that I was able to find, your car should have 8.5 US quarts of engine oil. If you siphoned 8.25 but did not let the oil from the filter drain out, it certainly looks like you had too much oil, a bit at least.

I've never tried how accurate the cluster reading would be. Also the new oil would be cold, you would have to wait some time to get the correct reading, not practical on a shop, would take too long.

What oil did you have before the change? Experts have shown that changing engine oil this soon introduces more wear, oil additives take some time to come to "full strength".
 
#4 ·
the whole issue is, the oil level sensor has a minimum and maximum level. cant remember the actually numbers but like 30-50mm with engine off and 45-65mm with engine running. may be a bit off, but if you add say 7 quarts of oil and that comes out to say 33mm with the engine off, the cluster will tell you the oil level is ok cause its within the parameters. if you add 1.5 quarts more the level may then be 50mm and its still ok.

for me i always use das when i do an oil change on a car with a oil level sensor as i can run the car and get the level about 5mm less then max spec, that way the customer wont have to return cause of a low oil level, and it takes in consideration that the vehicle consumes some oil
 
#5 ·
an update. after running the car around the block I did get a 'add 1 liter' message. This is counter to my thinking because I would think hotter oil would take up more volume (is there any thermal expansion with motor oil?) if anything. Shows how good my thinking is :rolleyes: I guess some of the oil goes somewhere besides the filter. I added .75 quart and got and have kept an 'OK' level. now I am probably at the lower end of acceptable level range with hot oil. This is 1/2 quart less than what came out.
Regarding my oil change. When I got the car recently I immediately did a change with 5-40 mobil 1 and just put in 0-40 mobil 1. (had to order it, no one around here stocked it).
Thanks for the responses
Larry
 
#6 ·
The 5w40 Mobil 1 Diesel Truck is an excellent oil however it does not meet the MB HT/HS requirements hence no official MB approval.

The 0w40 too is an excellent choice, it has an official MB approval and a slightly better cold flow capability vs the 5w40 (very slight).

Just my $.02 worth, the 5w40 would have been fine for an oil change cycle (assuming you arent running the car at it's performance limits).

The engine uses a coolant to oil heat exchanger, oil can hide in several places or air can be trapped in several locations as well until the engine is run for a few minutes above idle rpms.

If you have an extractor, I would suggest putting in the 8 liters and then check the level after a few minutes. If it's overfilled you can always suction of the slight excess or add as required.

DB
 
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