Go and slap hard to the mechanic who suggested to use CVT oil in 2006 passo.
CVT in passo came in 2009 onwards. Till 2008 models these are regular AT.
If you are using CVT oil in your AT (Automatic Transmission), then it will work like slow poison and in few months you may face transmission related issues.
You can use Dexron-II or Dextron-III rated ATF oil which are actually recommended for it.
Toyota D-II oil price is ~1000/L. ZIC ATF-III is only 630/L. Your car will take 3.5 or 4L. You better fill 3.5 and check the dip stick. Drive car for a while, then let it cool for couple of minutes while parking on straight level and then check the dip stick again. If it shows less, then add more accordingly.
Dips stick of Engine oil & Gear Oils are designed for Low & Max level. And technical distance between Low & Max mark is 25% of total oil capacity.
Means if dipstick shows oil level is in middle between Low & Max. and your cars takes 4L engine oil, then it means it need half liter oil to add in it.