Build Progress - VIN's and build dates
Hotshot
Joined: Apr 2013
Posts: 10,133
Likes: 665
From: NH
I go 5k miles between dealership (Motorcraft Syn-Blend) oil changes. I was chastised once already for this 'flawed' thinking but I'm very close to the oil change point for me, and my mpg is definitely off. I'd say by 3 mpg on the highway, and 2 mpg in the city.
Maybe my engine is leaching fuel into the oil more than it should? I've not done a sample test. All I know is that the oil is blacker than death on the stick and smells like burned diesel. However, the level is perfectly full and not over.
Maybe my engine is leaching fuel into the oil more than it should? I've not done a sample test. All I know is that the oil is blacker than death on the stick and smells like burned diesel. However, the level is perfectly full and not over.
Cargo Master
Joined: May 2007
Posts: 3,336
Likes: 4
From: Western New York
I go 5k miles between dealership (Motorcraft Syn-Blend) oil changes. I was chastised once already for this 'flawed' thinking but I'm very close to the oil change point for me, and my mpg is definitely off. I'd say by 3 mpg on the highway, and 2 mpg in the city.
Maybe my engine is leaching fuel into the oil more than it should? I've not done a sample test. All I know is that the oil is blacker than death on the stick and smells like burned diesel. However, the level is perfectly full and not over.
Maybe my engine is leaching fuel into the oil more than it should? I've not done a sample test. All I know is that the oil is blacker than death on the stick and smells like burned diesel. However, the level is perfectly full and not over.
Cargo Master
Joined: Dec 2003
Posts: 2,299
Likes: 2,060
From: Central MO
I would test that scenario with my 6.4L, but since my fuel economy sucks all the time, I don't know that I could tell the difference. 
BTW, I do 5k oil changes too, unless it has been 7 months, then I get it changed regardless. Sometimes it's only 3-4k miles. Due to a couple longer camping trips, I'm nearing my 5k miles in only 3 months this time.
BTW, I do 5k oil changes too, unless it has been 7 months, then I get it changed regardless. Sometimes it's only 3-4k miles. Due to a couple longer camping trips, I'm nearing my 5k miles in only 3 months this time.
Hotshot
Joined: Apr 2013
Posts: 10,133
Likes: 665
From: NH
I would test that scenario with my 6.4L, but since my fuel economy sucks all the time, I don't know that I could tell the difference.
BTW, I do 5k oil changes too, unless it has been 7 months, then I get it changed regardless. Sometimes it's only 3-4k miles. Due to a couple longer camping trips, I'm nearing my 5k miles in only 3 months this time.
BTW, I do 5k oil changes too, unless it has been 7 months, then I get it changed regardless. Sometimes it's only 3-4k miles. Due to a couple longer camping trips, I'm nearing my 5k miles in only 3 months this time.
Cargo Master
Joined: Dec 2003
Posts: 2,299
Likes: 2,060
From: Central MO
fordman, how does the 6.4L sound? I don't ever really see any around here. Our highway department purchased a fleet of 6.0L trucks and then replaced that fleet with 6.7L trucks, skipping the 6.4L. I think the 6.0L sounds like a real diesel, and the 6.7L sounds very quiet. Do you ever smell diesel from the tailpipe of the 6.4?
There is never a hint of diesel from the tailpipe, nor any smoke at all. The pipe is squeaky clean too!
Cargo Master
Joined: May 2007
Posts: 3,336
Likes: 4
From: Western New York
I would say the 6.4 is just a tad quieter than mid-way between the 6.0 and 6.7. It still has that diesel clatter, but not near as loud as the 6.0, but not quite as quiet as the 6.7. Before I bought it, I looked at an '05 6.0, and with both sitting next to each other, you couldn't even tell the 6.4 was running. I actually like the sound of the 6.4. I run a tank of biodiesel in it now and then (when I'm near the only bio pump in the area), and it's amazing how much quieter and smoother it runs with bio. I've also noticed fuel economy improves about 10-20% on the tank immediately AFTER a tank of bio.
There is never a hint of diesel from the tailpipe, nor any smoke at all. The pipe is squeaky clean too!
There is never a hint of diesel from the tailpipe, nor any smoke at all. The pipe is squeaky clean too!
Cargo Master
Joined: Dec 2003
Posts: 2,299
Likes: 2,060
From: Central MO
I don't notice a difference in HP, just that it runs a bit smoother and quieter. However, I don't use near the capabilities of the truck, even when towing my fiver, so I'm not sure I would notice. I don't think I've ever towed my fiver with a tank of bio though, either.
Fuel economy may be just a tad better on bio, but it's usually even better the tank after a run of bio. I'm wondering if it just cleans things out a bit maybe? I have no logical explanation. The nearest bio fuel is 30 miles away, so I don't get there often, and I don't think I've ever run two bio tanks in a row. I track all my fuel usage on fuelly.com, so I need to make note of which tanks are bio from now on.
I don't think I've ever towed my fiver with a tank of bio though, either.Fuel economy may be just a tad better on bio, but it's usually even better the tank after a run of bio. I'm wondering if it just cleans things out a bit maybe? I have no logical explanation. The nearest bio fuel is 30 miles away, so I don't get there often, and I don't think I've ever run two bio tanks in a row. I track all my fuel usage on fuelly.com, so I need to make note of which tanks are bio from now on.
Cargo Master
Joined: May 2007
Posts: 3,336
Likes: 4
From: Western New York
I am curious if the engine changes its tune when running bio and that is what affects the mileage on your first tank afterwards. Both of our previous cars were V-8's and after weeks of my wife only driving them I would open them up and reset the anti-knock sensor. After the initial clatter the power level would be higher and fuel mileage would increase.
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Cargo Master
Joined: Dec 2003
Posts: 2,299
Likes: 2,060
From: Central MO
I am curious if the engine changes its tune when running bio and that is what affects the mileage on your first tank afterwards. Both of our previous cars were V-8's and after weeks of my wife only driving them I would open them up and reset the anti-knock sensor. After the initial clatter the power level would be higher and fuel mileage would increase.
Cargo Master
Joined: Dec 2003
Posts: 2,299
Likes: 2,060
From: Central MO
As I was filling up with biodiesel this morning, it hit me as to what may be the reason for the increased fuel economy on the next tank after bio. Bio supposedly burns cleaner and doesn't need to regen as often, so I was thinking that the bio plugs the DPF less, causing a shorter or maybe less regen on the next tank. Just a thought...
