Forum Discussion
117 Replies
- HighbeamExplorerI commute 8 miles each way, each day, with a 7.3 diesel and monitor stuff like temperatures. With temps in the 40s my engine oil temp does not exceed 150 on my morning commute and due to the huge engine oil/coolant heat exchanger my coolant temp is always within a few degrees of the oil temps so no, it doesn't warm up.
I thought I would get smart and use the block heater as mentioned earlier in this thread a couple of times. NO! the block heater does not heat the engine 2/3 of the way, in fact, it only adds 30-40 degrees of temperature. After some research it turns out that this is common on cummins and powerstrokes. Seems 1000 watts of heat can't do much for a 1000# hunk of iron. That said, I plug in anyways because I get cab heat sooner and I believe that I save enough fuel to cover the electrical costs of running the heater.
I commute with my diesel for the huge majority of its miles. This is cheaper than owning a second commuter vehicle. I did the math. - Old-BiscuitExplorer IIIOP is considering a 2014 model diesel with the new DEF/SCR system and a 5 mile one way commute.
The 2014 Hemi would be a better choice. - macsplinterExplorer2005 Duramax with 111000 miles and a 6 mile commute each day. no problems. 1999 Dodge Cummings before that with no problem.
- gmcsmokeExplorer
bmanning wrote:
N-Trouble wrote:
bmanning wrote:
transamz9 wrote:
bmanning wrote:
Me Again wrote:
campingken wrote:
On the Olympic Peninsula in WA diesel is 30% more expensive than gas so that more than offsets the additional 15% better MPG of the diesel. Don't buy one to save money because you won't.
Diesels do like to me driven hard but don't put the pedal to the metal when you first start driving it. Putting the 10 - 12 quarts of oil that is sitting in the pan under extreme pressure is not a wise move.
Gasbuddy for Sequim
QFC
Gas 3.299 Diesel 3.849 or 16.7 percent more.
Chevron on 101
Gas 3.299 Diesel 3.799 or 15.2 percent more.
Safeway
Gas 3.369 Diesel 3.919 or 16.3 percent more.
Don't know how you came up with 30 percent?
Chris(who grew up in PA)
I've come to think that, at current fuel prices, it's pretty much a wash between gas & diesel when it comes to keeping it fed.
Example: my F250 gets about 12mpg running around town; let's assume I'm paying Safeway prices at $3.37/gal. At $3.92/gal for diesel, a diesel owner getting ~14mpg is spending the same on fuel.
I've read some (very honest) reports here of diesel owners getting around that figure (14) in-town. Of course, some of you get better, some perhaps a bit worse if your weapon of choice is a loaded 4x4 diesel dually with deep gears.
Even towing the spread isn't huge. Let's say my 5.4L got 8mpg towing a particular load. That'd be the equivalent of a diesel earning about 9.3mpg.
Funny, this can be spun a couple of different directions. The gasser guy can say, "See! There's little to no fuel savings with diesel!" whereas the diesel guy can say "I get twice the torque but spend the same on fuel!"
That all depends on the two engines you are comparing. There are gas motors that do better than the numbers you said in your post but there are also diesels that do better. Mine does ~18 (I've seen 17 and I've seen 19.5 on hand calculated tanks) in my town driving. I'm driving a Tundra 5.7 right now at work that's running in the 15 range. The 6.2 F250 we have is around 12.
No question, all comes down to the 2 being compared; I was just speaking in general terms. In your case, you have a great model year of the 5.9L for economy/power balance and a gasser would need to return about ~15.5mpg to match your fuel expenditure at ~18mpg (again using $3.37/gal for 87oct and $3.92/gal for diesel).
Who cares... All you guys are comparing what amounts to mice nuts when your talking a $40-50k truck. Choosing between gas/diesel should be based on towing needs, not nickel/diming fuel costs.
Congrats my friend, you clearly have a lot more money than I do! Fuel costs are a part of my monthly budget projections and have been pretty much since gas hit $3/gal plus some years back.
In the past I've run a small business and tracking every penny is still in my blood even though I'm a 9-to-5er now.
just quoting the quote - oilslickExplorer
wilber1 wrote:
I don't think lubrication is the real issue. Oil needs time at full operating temperature to get rid of moisture. This is true of all engines but the diesel has more mass to get up to temperature and more oil to heat when it gets there. Any damage would be internal corrosion over an extended period.
Also, the new trucks need some highway time to keep the DPF clean and avoid frequent regens. My truck probably spends 70% of its time towing and in 35,000 KM, I have yet to see a regen.
As to your original question, I don't think you would "kill" a diesel but it isn't the best way to operate one.
I would like to point out a couple of things. Ford and Chev don't make a manual transmission in a 3/4 or one ton truck so that leaves only the RAM Cummins diesel. In the paper version of the owners manual it states that if you do not use full synthetic 5W40 oil below -18C engine damage will occur.
While the Cummins engine is in "regen" there is no direct indication other than the fuel burn drastically reduced, if you have an EGT gauge you will see the increased exhaust temps displayed there. During regen exhaust gas is recirculated back into the intake just before the grid heater, if the engine is not at operating temp during regen that recirculated exhaust gas also contains unburnt diesel fuel which eventually runs down the cylinder walls and dilutes the oil causing the engine to "make oil" this unburnt fuel also runs back down the boost tube and collects at the exit to the precooler. Anyone start to see any problem yet?
If it's cold out the grid heaters will be on causing the unburnt fuel to become balls of hard carbon, these balls continue to grow in size until they can't get through the grid heater and then reduce the amount of airflow allowed into the engine. If a hard enough piece manages to get through the grid and out into the exhaust in one piece it can damage the turbo. Our 2011 3500 manual trans truck which was only driven on the hiway while towing at least 8000lb cargo trailer and often much heavier goose trailers even with a fast idle, winter front, synthetic oil, had problems from new. Oil change messages at 1500km and the oil so overfull and diluted with diesel fuel you wouldn't believe unless you saw it. The truck was forever at the dealer with exhaust codes, they changed a few O2 sensors but this is no way to treat a $15,000 engine if you have to replace it.
The truck would barely run in the end and the huge truck dealer here was no help. With about 30,000km on the truck I decided to tear it apart and document with pictures what I found. After my work the truck ran great and oil changes were in the range they should be with no oil dilution. The price was loss of warranty at 30,000km. I showed the pictures to the service manager, he was not surprised at all so he must have already seen this many times before yet would do nothing to correct it. I honestly don't think it was the dealer or the service manager, I think this came from Chrysler. They know the problem exists but the fix was the addition of DEF on the 2013 truck. I love the Ram trucks especially the 2013 with the Aisin trans but people need to know exactly what they are getting into before buying a Cummins powered truck and Chrysler won't tell you neither will the sales person. - wilber1Explorer
06Fargo wrote:
To the original question: diesels warm up slower because they have more metal mass, hold more lube oil which is also passing through a heat exchanger to the coolant plus they burn less fuel especially under light load to make the heat with. If you use synthetic oil with uber low pour point so the engine is lubricated what damage could occur?
I don't think lubrication is the real issue. Oil needs time at full operating temperature to get rid of moisture. This is true of all engines but the diesel has more mass to get up to temperature and more oil to heat when it gets there. Any damage would be internal corrosion over an extended period.
Also, the new trucks need some highway time to keep the DPF clean and avoid frequent regens. My truck probably spends 70% of its time towing and in 35,000 KM, I have yet to see a regen.
As to your original question, I don't think you would "kill" a diesel but it isn't the best way to operate one. - notevenExplorer IIITo the original question: diesels warm up slower because they have more metal mass, hold more lube oil which is also passing through a heat exchanger to the coolant plus they burn less fuel especially under light load to make the heat with. If you use synthetic oil with uber low pour point so the engine is lubricated what damage could occur?
- notevenExplorer IIITo the original question: diesels warm up slower because they have more metal mass, hold more lube oil which is also passing through a heat exchanger to the coolant plus they burn less fuel especially under light load to make the heat with. If you use synthetic oil with uber low pour point so the engine is lubricated what damage could occur?
- nevadanickExplorerI bet most, not all bought like i did and bought what i wanted.
- bmanningExplorer
N-Trouble wrote:
bmanning wrote:
transamz9 wrote:
bmanning wrote:
Me Again wrote:
campingken wrote:
On the Olympic Peninsula in WA diesel is 30% more expensive than gas so that more than offsets the additional 15% better MPG of the diesel. Don't buy one to save money because you won't.
Diesels do like to me driven hard but don't put the pedal to the metal when you first start driving it. Putting the 10 - 12 quarts of oil that is sitting in the pan under extreme pressure is not a wise move.
Gasbuddy for Sequim
QFC
Gas 3.299 Diesel 3.849 or 16.7 percent more.
Chevron on 101
Gas 3.299 Diesel 3.799 or 15.2 percent more.
Safeway
Gas 3.369 Diesel 3.919 or 16.3 percent more.
Don't know how you came up with 30 percent?
Chris(who grew up in PA)
I've come to think that, at current fuel prices, it's pretty much a wash between gas & diesel when it comes to keeping it fed.
Example: my F250 gets about 12mpg running around town; let's assume I'm paying Safeway prices at $3.37/gal. At $3.92/gal for diesel, a diesel owner getting ~14mpg is spending the same on fuel.
I've read some (very honest) reports here of diesel owners getting around that figure (14) in-town. Of course, some of you get better, some perhaps a bit worse if your weapon of choice is a loaded 4x4 diesel dually with deep gears.
Even towing the spread isn't huge. Let's say my 5.4L got 8mpg towing a particular load. That'd be the equivalent of a diesel earning about 9.3mpg.
Funny, this can be spun a couple of different directions. The gasser guy can say, "See! There's little to no fuel savings with diesel!" whereas the diesel guy can say "I get twice the torque but spend the same on fuel!"
That all depends on the two engines you are comparing. There are gas motors that do better than the numbers you said in your post but there are also diesels that do better. Mine does ~18 (I've seen 17 and I've seen 19.5 on hand calculated tanks) in my town driving. I'm driving a Tundra 5.7 right now at work that's running in the 15 range. The 6.2 F250 we have is around 12.
No question, all comes down to the 2 being compared; I was just speaking in general terms. In your case, you have a great model year of the 5.9L for economy/power balance and a gasser would need to return about ~15.5mpg to match your fuel expenditure at ~18mpg (again using $3.37/gal for 87oct and $3.92/gal for diesel).
Who cares... All you guys are comparing what amounts to mice nuts when your talking a $40-50k truck. Choosing between gas/diesel should be based on towing needs, not nickel/diming fuel costs.
Congrats my friend, you clearly have a lot more money than I do! Fuel costs are a part of my monthly budget projections and have been pretty much since gas hit $3/gal plus some years back.
In the past I've run a small business and tracking every penny is still in my blood even though I'm a 9-to-5er now.
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