The oil pump may be changed when the oil level light begins to glow. Buy the oil pump from the eBay motors and it will be replaced.
yes, you have. And change new seal too.
I CHANGE MY OWN OIL IN MY 1991 PREVIA. 5W30 IS WHAT I HAVE USED FOR YEARS. PREVIA JUST PASSED THE 334,000 KM MARK
5.8 quarts
the previa holds 6.1 quarts of oil
Bottom of the engine on the oil pan.
If the question is in reference to engine oil then according to the user manual on my 95 previa it is 10w 30.
SAE 10w30
under the front driver seat
The reservoir automatically replenishes oil in the oil pan if it is burned away. It was made for the consumer who doesn't change oil regularly.
underneathe the van by the oil filter.
approx 6.1lt
It doesn't. Your rings must be going, or a blow-by. You're lucky the Previa has a back up oil tank unda the hood :)