Below are the AMSOIL oil and filter recommendations for your 1999
1999 FORD Mustang 3.8L 6-cyl Engine Code 
Your 3.8L 6-cylinder engine turns out 190 hp @ 5,250 rpm and 220 lb-ft @ 2,750 rpm. It can also go from 0-60 in 6.97 seconds. This engine is a prefect candidate for AMSOIL synthetic motor oil and is worthy of taking excellent care of for the long term.
Here is what you need:
You need 5 quarts of AMSOIL 5W-20 Signature Series 100% Synthetic Motor Oil ASL-QT which you can learn more about here:
You need the AMSOIL nano fiber long life oil filter for your car and the model is EAO34.
To learn how to get wholesale dealer pricing and the fastest and easiest location to get Amsoil for your Ford Mustang go to where can I buy amsoil oil.
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