5W20 or 15W40?
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Joined: Oct 2004
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Do what your owners manual says.
Originally Posted by plumbguy
Why does the new 04 f-150 call for 5W20 motor oil. Is it OK to run a 15W40 instead?
Fleet Owner
Joined: Jan 2004
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From: Brentwood,CA
Originally Posted by zeusdog
All I know is my 15 year old Bronco calls for 5W20 so I guess they've been using it for years. If you don't use the oil that your owners manual calls for your run the risk of voiding your warranty.
the answer is yes if you want to but why use 5w20 or 5w30 and no it has been gone over and over you can void your warranty by using something else as long as it is api certified
New User
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It's not just the 'warranty' (boy, that irritates me when people use that as a 'reason' without explaining the real reason!).
The newer engines have much tighter tolerances than the older engine designs. Also, the 4.6 and 5.4 have extremely tiny orifices draining the oil from the top of the engine back down to the pan. If you use too thick of an oil, the orifices do not flow fast enough and the bottom of the engine starves for oil and you end up burning up the bottom end by about 100K miles. So you can use the 15W-40 if you don't mind rebuilding the engine at 90K-100K, otherwise use the oil designed and specified to run in these motors. Even a 10W- oil will be too thick. If you insist on running a thicker oil than the 5W-20, use the 5W-30 but nothing thicker.
I run 10W-40 in my 11 year old Ranger and I used to use 20W-50 in my older big block pickups, but I'm going to stick with 5W-20 in my 5.4 F150.
The newer engines have much tighter tolerances than the older engine designs. Also, the 4.6 and 5.4 have extremely tiny orifices draining the oil from the top of the engine back down to the pan. If you use too thick of an oil, the orifices do not flow fast enough and the bottom of the engine starves for oil and you end up burning up the bottom end by about 100K miles. So you can use the 15W-40 if you don't mind rebuilding the engine at 90K-100K, otherwise use the oil designed and specified to run in these motors. Even a 10W- oil will be too thick. If you insist on running a thicker oil than the 5W-20, use the 5W-30 but nothing thicker.
I run 10W-40 in my 11 year old Ranger and I used to use 20W-50 in my older big block pickups, but I'm going to stick with 5W-20 in my 5.4 F150.
Fleet Owner
Joined: Jan 2004
Posts: 26,007
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From: Brentwood,CA
however the oil clearance has never changed in the modular engines from the time they were released the specs are still the same just a heavy oil cause hard starts bad mpg bottom wear oil pump stress and the oil drains back down through very small holes and it tends to pool up at high rpm starving the bottom end the switch starting in 2001 was to get a higher fleet mpg rating the 5w20 also protects better than the 5w30 just look at some of the uoa's here on the website.
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The warranty is important.
Originally Posted by RockyTwo
It's not just the 'warranty' (boy, that irritates me when people use that as a 'reason' without explaining the real reason!).
The newer engines have much tighter tolerances than the older engine designs. Also, the 4.6 and 5.4 have extremely tiny orifices draining the oil from the top of the engine back down to the pan. If you use too thick of an oil, the orifices do not flow fast enough and the bottom of the engine starves for oil and you end up burning up the bottom end by about 100K miles. So you can use the 15W-40 if you don't mind rebuilding the engine at 90K-100K, otherwise use the oil designed and specified to run in these motors. Even a 10W- oil will be too thick. If you insist on running a thicker oil than the 5W-20, use the 5W-30 but nothing thicker.
I run 10W-40 in my 11 year old Ranger and I used to use 20W-50 in my older big block pickups, but I'm going to stick with 5W-20 in my 5.4 F150.
The newer engines have much tighter tolerances than the older engine designs. Also, the 4.6 and 5.4 have extremely tiny orifices draining the oil from the top of the engine back down to the pan. If you use too thick of an oil, the orifices do not flow fast enough and the bottom of the engine starves for oil and you end up burning up the bottom end by about 100K miles. So you can use the 15W-40 if you don't mind rebuilding the engine at 90K-100K, otherwise use the oil designed and specified to run in these motors. Even a 10W- oil will be too thick. If you insist on running a thicker oil than the 5W-20, use the 5W-30 but nothing thicker.
I run 10W-40 in my 11 year old Ranger and I used to use 20W-50 in my older big block pickups, but I'm going to stick with 5W-20 in my 5.4 F150.
New User
Joined: Nov 2004
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Zues-
In my mind, someone saying 'warranty' is just like someone saying 'Because I said so!!'. It just doesn't cut the mustard in my analytical mind. I want the real reason, not just some parrot squawking 'warranty'. And you yourself have incessantly whined about how the warranty isn't worth the paper it's written on, so why should a worthless warranty be sufficient reason for anything?
And I'm not disagreeing with the type of oil to use, I just like hearing the real reason and not some parrot hollering 'warranty'.
In my mind, someone saying 'warranty' is just like someone saying 'Because I said so!!'. It just doesn't cut the mustard in my analytical mind. I want the real reason, not just some parrot squawking 'warranty'. And you yourself have incessantly whined about how the warranty isn't worth the paper it's written on, so why should a worthless warranty be sufficient reason for anything?
And I'm not disagreeing with the type of oil to use, I just like hearing the real reason and not some parrot hollering 'warranty'.
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Postmaster
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From: Marion, VA
I used to think thicker was better until a read an article that made sense to me. It said most engine wear happens after you start the engine but before the oil light goes out or the oil gauge moves. The wearing surfaces have very little oil on them until oil pressure pushes it there and this results in bearing wear. The thinner oil gets to the bearings faster and you have less wear.
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Joined: Mar 2004
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From: CT
plumbguy,
I had my truck to the dealer for a miss. It was diagnosed with a bad coil at first. Tech finally called the 'hotline' because they could not fix the miss. The super tech on the hotline asked if I had changed my oil and what oil I used if I did. Reason - The oil is some how used to control timing, change the viscosity and you change how it pumps. May be a bunch of crap because I had the right oil in the truck and they needed to change all the spark plugs.
I had my truck to the dealer for a miss. It was diagnosed with a bad coil at first. Tech finally called the 'hotline' because they could not fix the miss. The super tech on the hotline asked if I had changed my oil and what oil I used if I did. Reason - The oil is some how used to control timing, change the viscosity and you change how it pumps. May be a bunch of crap because I had the right oil in the truck and they needed to change all the spark plugs.
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Joined: Oct 2004
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What is with the insults?
Originally Posted by RockyTwo
Zues-
In my mind, someone saying 'warranty' is just like someone saying 'Because I said so!!'. It just doesn't cut the mustard in my analytical mind. I want the real reason, not just some parrot squawking 'warranty'. And you yourself have incessantly whined about how the warranty isn't worth the paper it's written on, so why should a worthless warranty be sufficient reason for anything?
And I'm not disagreeing with the type of oil to use, I just like hearing the real reason and not some parrot hollering 'warranty'.
In my mind, someone saying 'warranty' is just like someone saying 'Because I said so!!'. It just doesn't cut the mustard in my analytical mind. I want the real reason, not just some parrot squawking 'warranty'. And you yourself have incessantly whined about how the warranty isn't worth the paper it's written on, so why should a worthless warranty be sufficient reason for anything?
And I'm not disagreeing with the type of oil to use, I just like hearing the real reason and not some parrot hollering 'warranty'.
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