1KR Fe when built recommend the usage of 0w20 oil in colder regions till 2005.
And after 2005 0w20 and 5w30 was combined us d in both Vitz and Passo and some IQ models.
And after 2007 0w20 was recommended for all jdm 1KR engines for best economy and performance.
And in British domestic model which uses Bosch ecus and without egr systems uses 5w30 as standard and 5w40 as normal oil viscosity.
All 1 kr from 2005 till 2010 in Toyota Vitz specifically KSP 90 / 92 uses 3.6 Liters of engine oil with oil filter replacemwnt.
And passo from 2003 onward to 2010 KGC 10 series uses same oil quantity.
Where as Vitz from 2010 till 2014 KSP130 series uses 3.2-3.4 liters with oil filter replacement.
And passo 2010 till2014 uses the same oil quantity.
Now comes the new gen 1 KR they all uses 3Liter engine oil with oil filter