A 1993 Ford Aerostar would have come from the factory with ( 5W-30 )
According to the 1996 Ford Aerostar Owner Guide : ( 5W-30 ) is the preferred oil
On a 1993 Ford Aerostar , 4.0 liter V6 engine : With engine oil filter change : I ASSUME it is the same as the 4.0 in my 1995 Ford EXPLORER ( 4.7 litres / 5.0 U.S. quarts of 5W-30 engine oil )
10w30 weight.
Could be a bad oil sending unit Have you got oil int engine. it not, you got a big problem.
10w30
Ford Aerostar
The 1997 Ford Aerostar oxygen sensor is screwed into the exhaust pipe. It is about even with the rear of the oil pan.
5W-30
In a 1993 Ford Aerostar : Either the 3.0 liter V6 or the 4.0 liter V6 ( the 3.0 liter V6 engine has the oil filter on the drivers side of the engine and the 4.0 liter V6 has the oil filter on the passenger side of the engine , just something I noticed and use to tell the difference at a glance )
How many miles on vehicle--internals may be worn Rings, valve seals/guides etc. What weight oil are you using--may be able to go to a heavier weight
On a 1989 Ford Aerostar : I believe the oil pressure sending unit for the oil pressure gauge on the 4.0 liter EFI , V6 engine is on the drivers side of the engine below the power steering pump