F-150forlife

Once the search bar is bugged I can't seem to get an answer. I have two questions for my 2004 f150 5.4 with 92,xxx miles.

1. What oil would be better for my area, northern California butte county which is about 15-110 degrees in climate.
5w-30 or 10w-30? I know 15w is for volcanoes so is 10w a happy medium for cold and hot temp or should I stick with 5w?
I know I want 30 because it's thicker than the recommended 20 and it'll help my engine a lot better as read on previous oil threads.

2. What oil would be better for my engine: full synthetic or high mileage?
I know my truck is above 90k but I've heard people using synthetic blend and full synthetic on their trucks at 150,xxx miles so what would be the better choice?

otto457

This should help with the viscosity. Both a 10w-30 and 5w-30 are the same at operating temps, your cold flow is worse with the 10w and a 5w is still too "thick" at start up than what the engine truly needs.
http://www.bobistheoilguy.com/motor-oil-101/

What are your driving habits, etc? No need for a HM unless there's an issue. I could also go into the whole "synthetic" deal but that would take pages.

F-150forlife

My driving habits are normal IMO; I use cruise control most of the time half hwy half city driving mainly. I do have the occassional wot here and there but no 0-60's or freak driving.

I know I want something w-30 (5 or 10) just trying to decide by tomorrow so I can correct a mistake my parents mechanic made. My grandpa told me to put in 10w-30 high mileage to protect from engine wear. I keep thinking full synthetic for the little bit of mpg improvement it gives you.

Any thoughts?

F-150forlife

Well after reading that website I decided that 5w-30 full synthetic is the way to go. SL or SM rated and well to my understand any oil company is good so I'll goo with a slightly cheaper synthetic to save a little money. Same motorcraft oil filter though.

Thanks for the post! I guess you do learn something new everyday! :thumbs up: