using 5w-40 questions
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Joined: Jan 2012
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using 5w-40 questions
so im looking to be in a new to me truck by next week. when i buy used vehicles the first thing i do is changed the engine oil (i change the other boxes asap as well but later). here is my delema, i have been driving diesels since i got my license and have always used 15w-40 or 5w-40 oil in either ci-4+ or the newer cj4. these oils are also sm rated. recently i bought a 30 gallon drum of 5w-40 cj4/sm full synthetic oil. with three diesels and a lot of miles it lets me stock up some with out going over board. now i have sold my diesel and am buying an 06 5.4, i think the oil is supposed to be 10w-30 or 5w-30, i dont know what the api is on it. thats question one, what is the latest oil for these engines. second is the 5w-40 i have too heavy? will it cause problems? if so what might happen? or will i be fine using it. the truck has 160k on the clock which might make a difference.
what have others done? anyone use a 40 weight oil in their truck?
what have others done? anyone use a 40 weight oil in their truck?
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Joined: Oct 2010
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From: King of Prussia, PA
5w-30 is what is used. There was a thread on here a few weeks back on the discussion of using a heavier oil. Some guys are using it in warmer climates.
Do a search or hopefully someone will post the link for you.
I got rid of my diesel 1 1/2 years ago. I miss the power, torque and fuel mileage but not the fuel bills.
Do a search or hopefully someone will post the link for you.
I got rid of my diesel 1 1/2 years ago. I miss the power, torque and fuel mileage but not the fuel bills.
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From: Elmhurst, IL
'08f150stx
Joined: Jul 2010
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From: Wisconsin
5w-20 Motorcraft Synthetic Blend is what the manufacturer recommends.
The oil topic comes up quite often. Any quality brand oil, and a Motorcraft filter (or equivalent). I believe the Motorcraft has an anti siphoning valve and only a filter with that feature should be used. That is what the engine was designed to run with. The oil weight, well I have not owned a factory engine that was designed to run with 40w for some time (a couple decades).
The oil topic comes up quite often. Any quality brand oil, and a Motorcraft filter (or equivalent). I believe the Motorcraft has an anti siphoning valve and only a filter with that feature should be used. That is what the engine was designed to run with. The oil weight, well I have not owned a factory engine that was designed to run with 40w for some time (a couple decades).
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Joined: Jan 2012
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hmm, this is a problem. im not worried about using the 5w-40, that can go in the diesels we have. however the lowest weight oil i can get from this company is 5w-30 which is still too heavy apparently. i have been using this oil in others apps and really happy with it. i dont like the idea of changing brands, would 5w-30 be too much too?
