Focus 2008. The recommended oil to use in Your 2008 Ford Focus iS4.5 quarts of SAE 5W-20. Whether or not You want to use conventional or synthetic is up to You but the synthetic is probably better for long term engine health. You can pick up A5 quart bottle of most motor oils from Your local auto goods store or even Walmart for around FordFocus Tech Discussions. General Technical Chat Does anyone have any info on how to change the transmission gear oil in an 08' Focus? Haynes manuals are not available for it as of yet. have the part # handy, but once used it in my Mazda Miata with good results). If anyone can help with the reccomended fluid/oil type and where the AMSOILOE 5W-20 100% Synthetic Motor Oil. Product Code: OEMQT-EA. 5.0 (80 Reviews) Fights sludge and deposits with 100% synthetic formulation. 47% more wear protection1 than required by the GM dexos1 Gen 2 specification. 100% protection against LSPI2 in the engine test required by the GM dexos1 Gen 2 specification. iwDgN.