on sl 500 , 550 can you suck out the oil via hole where measure level oil? or is that not good ?

Yes, as long as you confirmed you have a dipstick: https://mbworld.org/forums/c-class-w...il-change.html

Actually, the SL500 (M113) engine has a dedicated tube for oil extraction. It does not use a dipstick, but rather the oil level is electronically measured.

WRT extracting through the dipstick tube, that is the specified way to drain the oil for most engines with the oil filter on top.

Perhaps, but I disagree. I like warming the oil up, then removing the panels and draining the oil from the crankcase. This assures you get all of the oil and any debris particles. JMHO but if you have access to a lift as I do, this also allows you to perform a good inspection of the entire undercarriage.

Also, I have the V6 engine if that makes any difference. It does have a traditional dipstick.

Fair enough, WIS calls for top extraction though for the M276 at least.

Understood and probably what the dealers do as it is far less time and labor involved.

this page is R231 page , dont mix up with R230

did it old fashion way , lift up car and drain it , took less than 20 min all operation , very easy on this engine model do it.

Both methods are completely fine if your vehicle comes with a dipstick. However I find inconsistencies with how much oil is needed to reach full depending on if I drain using drain plug or oil extraction. Just make sure oil level is correct after finish. It is easier to use drain plug to ensure full drain. Using oil extraction tube you may not actually push all the way down to the bottom, or your extraction tube can curl in bottom of pan and not extract all the oil properly.

Sure. I always adjust the extraction tube as I approach the end of the draining. I've always gotten 6.5+ liters from my engines using the suction method. Capacity is 6.5 liters for the M276, but I always fill to the top of the limit on the dipstick.

Good to hear : )

sl500 this engine is 8,5 liters total