Mora da se ispere, inace, sinteticko ulje koje je redje i bolje cisti motor, ima da pokupi sve naslage koje je ostavilo mineralno ulje i eto VELIKIH problema, te odvojene naslage mogu da zapuse uljne kanale i slicno. Ljudima se desavalo da motor propisa na sve strane i krene da trosi abnormalne kolicine ulja.
Sinteticko ulje ima totalno drugacije aditive i bolje cisti motor, bolje ga hladi...
Motor nema potrebe ispirati kad se prelazi sa sintetickog/polusintetickog na mineralno jer ostavlja daleko manje naslaga (taloga)
Sta kaze engine bible:
"If you've been driving around with mineral oil in your engine for years, don't switch to synthetic oil without preparation. Synthetic oils have been known to dislodge the baked-on deposits from mineral oils and leave them floating around your engine - not good. I learned this lesson the hard way! It's wise to use a flushing oil first."
Znaci, obavezno ispiranje.
http://www.chris-longhurst.com/carbibles/engineoil_bible.html