Is that the model that has 2 drain plugs? Maybe it is the Mustang GT 5.0. Check that the first time you change oil yourself.
What engine speed does your GT run at 75 mph on the highway? If the rpm's are high say 2800+, then 5w-20 is the best choice because oil that's pumped up to the cams needs to drain back down to the sump fast. If highway rpm's are lower say 2300, then either grade is ok and 5w-30 will reduce consumption on cross country trips.
What engine speed does your GT run at 75 mph on the highway? If the rpm's are high say 2800+, then 5w-20 is the best choice because oil that's pumped up to the cams needs to drain back down to the sump fast. If highway rpm's are lower say 2300, then either grade is ok and 5w-30 will reduce consumption on cross country trips.
