[Steelman917]

Hi there, need a bit of help. I currently have a 91 Ford Mustang LX 2.3L convertible and its sitting at 145k miles. Should I be using a heavier weighted oil with that much mileage on it or should I stick with the 10w40?

[EagleAutosports]

Hiya, I see this is your first post. Welcome to the site.
As long as the oil pressure is at least 20-25 pounds once it's at operating temperature it should be fine.

[b_chandler]

10w-40 is fine.

[edzdallas79]

i have a 92 2.3l. i've heard that ford recommends semi-synthetic. is this true?

[DBT4220]

run straight 30w and if your car is older and has a little bit of blow by (worn rings) use 20w-50