5 w 30
My ( 1991 ) 5.0 LX Ford Mustang always used 5W-30 as recommended
The 1990 Ford Mustang 2.3L SOHC had 88HP
Where is ac low pressure service port on a 1990 ford mustang
According to the 2007 Ford Mustang Owner Guide : ( 5W-20 ) for the 4.6 liter 3V engine
no
It will bolt in, however, you will run into problems with the onboard computer. You will have to reprogram, or maybe even change it.
According to my Chilton's Auto Repair Manual : A 1990 Ford Mustang has a ( 15.4 U.S. gallon gas tank )
Viscosity SAE 5W-30 V6 Engines Viscosity SAE 5W-20 V8 Engines
Should drop right in...same engine.
The 1990 Ford Mustang 5.0 liter V8 engine is rated at ( 225 horsepower from the factory )
( 5W-20 ) according to the 2007 Ford Mustang Owner Guide for the 4.6 liter 3V engine
Maybe put the key in?