Not 100% sure but on newer ones it's 5w-20(most likely) and on older ones it's 5w-30. Any auto parts store could tell you for sure.
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On a 2004 Ford Explorer :
With engine oil filter change :
The 4.0 liter SOHC , V6 engine takes ( 5.0 U.S. quarts / 4.7 litres of 5W-30 )
The 4.6 liter V8 engine takes ( 6.0 quarts / 5.7 litres of 5W-20 )
* according to the Owner Guide
The 2004 Ford Explorer has a V6 engine.
might need to check your engine soon
The 2004 Ford Explorer has a 4.0 L base engine size.
The 2004 Ford Explorer's engine produces 210 hp @ 5100 rpm.
The 2004 Ford Explorer's engine produces 254 ft-lbs. @ 3700 rpm.
On a 2004 Ford Explorer : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
215/65/r17 :)
No. The 2004 Ford Explorer had the 4.0L SOHC V6 engine, while the 1996 Ford Explorer had the 4.0L OHV V6 engine. The 2004's V8s were a 4.6L V8, while the '96's V8s were the 5.0L V8. So, no....
For the 4.0 liter V6 engine ( 5W-30 ) For the 4.6 liter V8 engine ( 5W-20 ) According to the 2004 Ford Explorer Owner Guide
Absolutely , the engine in a 2004 Ford Explorer needs an engine oil filter ( or your engine will only last a few seconds while the oil pumps out on to the ground )
The only factory engine in a 2004 Ford Explorer Sport Trac is the 4.0 liter Single Over Head Cam , V6 engine which has ( 6 engine cylinders )
4.0 liter V6 engine ( 5W-30 ) 4.6 liter V8 engine ( 5W-20 ) According to the 2004 Ford Explorer Owner Guide