There are loooong discussions on this under the search button, but I think the general consensus is for any engine, (US, Japan, German, whatever), and for any number of cylinders, change oil and filter while hot at 3000 mile intervals. Some argue that the synthetics last longer, but to me dirt is dirt, no matter how slippery the oil in which it is suspended. I change oil this way on my celica gts, and so far the engine has lasted 280,000 hard driving miles. Hope this helps.
2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)
Click to see 87 300E