WHAT determines WHEN you change it ? ... I do the eyeball, smell and feel-test more than actual mileage.

Someone I know is going to me but I just checked my last THREE changes(as far as mileage) .... and this opened-my-eyes ....

4246, 5464 and ..... 9016

...and the last two did not really need a change ... I just felt my little 4 banger 5 speed Caravan deserved some fresh-oil.