I know it will hold the usual 300E oil change ... I will look but I believe it is either 8 or 10 quarts.
The Liqivac isn't perfect but it does the job. Let me explain - I use a thicker tube that goes into the dipstick, hardware store item. It is best not to use with really hot oil because the tubes get too soft. Best also with warm oil to get a flow. Don't over tighten or over pump for intense vacuum.
Overall it is great. I used it to suck out ATF. brake fluid, PS fluid etc.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)