MPG Diesel vs. Gas
09-13-2010, 12:13 PM
#16
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09-13-2010, 03:32 PM
#17
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With to-day's advanced EFI technology, gas engines SHOULD last much longer than they did just 10 years ago.
A properly running and maintained modern V-8 gasser will barely darken good oil between oil changes, unlike most (not all) diesels will.
This has to improve the longevity, plus reduce friction, in general.
Gassers also tend to be a better engine to use in winter climates.
I drive diesels mainly because they can get out of their own way in a big truck.
Mark.
A properly running and maintained modern V-8 gasser will barely darken good oil between oil changes, unlike most (not all) diesels will.
This has to improve the longevity, plus reduce friction, in general.
Gassers also tend to be a better engine to use in winter climates.
I drive diesels mainly because they can get out of their own way in a big truck.
Mark.
09-13-2010, 10:46 PM
#18
The fleet of 200 plus gas trucks where I worked before would be sold off at 300,000km (180something thousand miles) they would not touch a diesel truck for their crew trucks.
Of the diesel pickups they did own (for mechanics) they were usually in the shop for maintance more then the gasser. A modern gas engine with regular oil changes will last as long or longer then a modern diesel under the same driving conditions.
That is reality setting in, Yes the gas trucks tow heavy, yes they are heavily abused, and yes they are run some times days on end ideling in sub zero temps. Yes they get the crews home at the end of the day.
I like my diesel but to buy a new one would be a hard choice, considering the reliabilty issues of a modern diesel plant, the cost of repairs if something does happen and the ability (or lack of)of the mechanics charged with fixing them. Not to mention the poor milage of a modern diesel. The days are gone where a diesel in a pickup truck ruled the mpg, longivity and power wars of past.
Now for specialized applications they still work good for, but for the average diesel owner they are not a feasable vehicle for everyday use.
I will stick my neck out here and say the vast majority of guys who say they get 20mpg in their 3rd gen look at the over head and think that us what they are getting. If your not seeing 1000km (600miles) + per tank then you are not near the 20mpg US. I have talked to many people over the past couple years who all say they get 20mpg up to 30mpg towing, when I asked them how many kilometer per tank they get they usually say 6-650km ( 400miles) which is no where near 20mpg US. Think and dream what you want but a diesel engine has lots it's abiltiy to stay out in front.
Of the diesel pickups they did own (for mechanics) they were usually in the shop for maintance more then the gasser. A modern gas engine with regular oil changes will last as long or longer then a modern diesel under the same driving conditions.
That is reality setting in, Yes the gas trucks tow heavy, yes they are heavily abused, and yes they are run some times days on end ideling in sub zero temps. Yes they get the crews home at the end of the day.
I like my diesel but to buy a new one would be a hard choice, considering the reliabilty issues of a modern diesel plant, the cost of repairs if something does happen and the ability (or lack of)of the mechanics charged with fixing them. Not to mention the poor milage of a modern diesel. The days are gone where a diesel in a pickup truck ruled the mpg, longivity and power wars of past.
Now for specialized applications they still work good for, but for the average diesel owner they are not a feasable vehicle for everyday use.
I will stick my neck out here and say the vast majority of guys who say they get 20mpg in their 3rd gen look at the over head and think that us what they are getting. If your not seeing 1000km (600miles) + per tank then you are not near the 20mpg US. I have talked to many people over the past couple years who all say they get 20mpg up to 30mpg towing, when I asked them how many kilometer per tank they get they usually say 6-650km ( 400miles) which is no where near 20mpg US. Think and dream what you want but a diesel engine has lots it's abiltiy to stay out in front.
09-14-2010, 02:00 AM
#19
Back when I had my '03 3500 QCSB it was compared to my boss' '05 1500 QCSB after lunch one day ....
He loved his truck but complained about mileage, telling me that on the highway it might break 10 MPG unless he towed his 2 jet ski's and it would drop to 7 or 8 MPG on a good day. He asked me about my mileage and I told him on the highway I was getting a solid 13.5 MPG at 75 MPH and I was knocking on 15 MPG if I dropped it down to about 62 MPH. Towing a small trailer with jet ski's on it wouldn't affect my mileage much because it really wasn't that much of a load.
After he picked his jaw up from the ground we talked diesel, especially VW Passat's because he was more of an "in-town" kind of guy. I don't think he would have made the plunge into diesel, even after hearing 35 plus MPG and costing less than a hybrid.
Kris
He loved his truck but complained about mileage, telling me that on the highway it might break 10 MPG unless he towed his 2 jet ski's and it would drop to 7 or 8 MPG on a good day. He asked me about my mileage and I told him on the highway I was getting a solid 13.5 MPG at 75 MPH and I was knocking on 15 MPG if I dropped it down to about 62 MPH. Towing a small trailer with jet ski's on it wouldn't affect my mileage much because it really wasn't that much of a load.
After he picked his jaw up from the ground we talked diesel, especially VW Passat's because he was more of an "in-town" kind of guy. I don't think he would have made the plunge into diesel, even after hearing 35 plus MPG and costing less than a hybrid.
Kris
09-14-2010, 06:40 AM
#20
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That makes my mind up. I will keep my 12 valve forever. I don't have a mileage calculator. I hand calculate, and average 18 to 18.5 locally, and break 20 on interstate.
I do agree with what is being said here- if you put aside your affection and allegiance to diesels, and if you don't tow heavy for a living or for the majority of your miles, it is impossible, at the cost of new trucks, to justify the cost of a diesel. A gas engine will cost you less, and perform nearly as well.
My father went through this thought process. He had a 95 F250 powerstroke, and regardless of all the flaming that they get, that truck pulled well, and compared to my stock 94 12 valve, it pulled much stronger than mine. He had it for 8 years, putting 63,000 miles on it. He got tired of the diesel maintenance costs, and sold it. He bought a V-10 Superduty, 6 speed, 4.30 axles. That truck does pretty sorry on fuel, but in 7 years, he has only driven it 18,000 miles. He doesn't even feel the low gas mileage. It pulls strong, and has cost virtually nothing to maintain, other than oil changes. And, he paid considerably less for it, than if it had a diesel option. For him, the gas engine made better sense, and he can tow as well as the powerstroke did.
To each his own, and I am just as loyal as the next guy about my diesel. But, I will admit it is out of sentiment and love, not necessarily the most practical choice to make. And I only paid $6000 for mine.
I do agree with what is being said here- if you put aside your affection and allegiance to diesels, and if you don't tow heavy for a living or for the majority of your miles, it is impossible, at the cost of new trucks, to justify the cost of a diesel. A gas engine will cost you less, and perform nearly as well.
My father went through this thought process. He had a 95 F250 powerstroke, and regardless of all the flaming that they get, that truck pulled well, and compared to my stock 94 12 valve, it pulled much stronger than mine. He had it for 8 years, putting 63,000 miles on it. He got tired of the diesel maintenance costs, and sold it. He bought a V-10 Superduty, 6 speed, 4.30 axles. That truck does pretty sorry on fuel, but in 7 years, he has only driven it 18,000 miles. He doesn't even feel the low gas mileage. It pulls strong, and has cost virtually nothing to maintain, other than oil changes. And, he paid considerably less for it, than if it had a diesel option. For him, the gas engine made better sense, and he can tow as well as the powerstroke did.
To each his own, and I am just as loyal as the next guy about my diesel. But, I will admit it is out of sentiment and love, not necessarily the most practical choice to make. And I only paid $6000 for mine.
09-14-2010, 10:42 AM
#21
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My 2007 GMC classic k1500 got 15mpg at it's very best, and got 10-11mpg towing my car trailer.
My 2007 ram 2500 2wd got 22mpg (750+ miles before next fill up) at it's very best and got 15-16 towing my car trailer.
My 2008 ram 3500 4x4 drinks fuel compared to my old 2500 2wd, but it still gets better than my old GMC at almost double the weight.
My 2007 ram 2500 2wd got 22mpg (750+ miles before next fill up) at it's very best and got 15-16 towing my car trailer.
My 2008 ram 3500 4x4 drinks fuel compared to my old 2500 2wd, but it still gets better than my old GMC at almost double the weight.
09-14-2010, 07:51 PM
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I compared mine to a man with the same year gasser truck, driving the same way in a similar climate (and we owned similar trailers).
I ran the numbers: So long as diesel was no more than 50-cents more than gasoline, then fuel cost was a wash.
The real test is how long each will last without major engine repair AND still perform like new (not just pass emissions test, but really work).
If a Cummins is left alone (and maintained) we already know that MTBO is 350k. On a gasser I am assuming that number will be around 200k.
The difference in fuel cost is just a few cents per mile. So the real cost difference is in initial purchase price, first, and life expectancy, second.
The greater number of miles for the diesel pretty well takes care of the purchase price problem through life expectancy. In service fuel economy is icing on the cake (at my mpg).
Now, for those who dog the these trucks this won't work. 500HP against what Dodge designed for 325 means shorter component life. New fuel injectors, alone, give the gasser an advantage. Having to "build" an automatic is the same problem. There is no free lunch.
Stock vehicle, light on the controls, strict maintenance schedule, keep it garaged. Nothing new here in fifty years . . that is the vehicle that lasts the longest.
Fuel economy is just a problem sub-set of Economy. It might be less than 20-cents of a 90-cent per mile vehicle. The difference between the gasser and the diesel might be a few pennies. If the other capabilities aren't accounted for (and I.R.S. deductible miles aren't present), then a pickup itself is hardly worth it. So the difference between gasser and diesel is really not so important UNLESS one is doing everything to make them last longer. Turning them over every few years is a case made in favor of a gasser. Same with towing about 5k annually.
.
.
I ran the numbers: So long as diesel was no more than 50-cents more than gasoline, then fuel cost was a wash.
The real test is how long each will last without major engine repair AND still perform like new (not just pass emissions test, but really work).
If a Cummins is left alone (and maintained) we already know that MTBO is 350k. On a gasser I am assuming that number will be around 200k.
The difference in fuel cost is just a few cents per mile. So the real cost difference is in initial purchase price, first, and life expectancy, second.
The greater number of miles for the diesel pretty well takes care of the purchase price problem through life expectancy. In service fuel economy is icing on the cake (at my mpg).
Now, for those who dog the these trucks this won't work. 500HP against what Dodge designed for 325 means shorter component life. New fuel injectors, alone, give the gasser an advantage. Having to "build" an automatic is the same problem. There is no free lunch.
Stock vehicle, light on the controls, strict maintenance schedule, keep it garaged. Nothing new here in fifty years . . that is the vehicle that lasts the longest.
Fuel economy is just a problem sub-set of Economy. It might be less than 20-cents of a 90-cent per mile vehicle. The difference between the gasser and the diesel might be a few pennies. If the other capabilities aren't accounted for (and I.R.S. deductible miles aren't present), then a pickup itself is hardly worth it. So the difference between gasser and diesel is really not so important UNLESS one is doing everything to make them last longer. Turning them over every few years is a case made in favor of a gasser. Same with towing about 5k annually.
.
.
10-06-2010, 04:01 PM
#23
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Respectfully, I have to disagree with your last paragraph. I do agree that today's gas engines are lasting much longer. But, I think that it is a still a stretch for a gas engine to go 200,000 or 250,000 miles, while the typical diesel can double that if cared for, and more. Perhaps when comparing apples to apples in your application, and both types are being beaten on, they are lasting the same. But in many instances, a gas engine just isn't built as heavy or able to handle the miles and stress like a diesel engine does.
I would expect most gas engines with moderate care to go at least 200,000.Our 95 Safari van with a 4.3 was going strong when we went larger with our 98 Expedition, it had close to 190,000 miles and was not using any oil or showing any signs of quitting.
Our old 91 Explorer that our kids drove had a rough life. 3 teenage drivers. The 4.0 in it was running good at 184,000 and using no oil when the transfer case went out. I didn't want to buy a new transfer case so we gave it away.
I sold my Geo Prism with 300,000+ mi's on it. As far as I know the guy is still driving it. It did need new valve stem seals.
Our old 98 Expedition with a 5.4 has over 240,000 mi's on it now. We gave it to our daughter and Son-In-Law. They love it, it saw a lot of towing with our boat and is still going strong. When we towed down to LOTO this year we did only average about 9-10mpg. That was with the cruise set at 65-70mph, 6 people on board and a full Thule carrier on the roof.
We bought a 2006 Expedition with 5.4. It gets 15-17 average around town and will pull our 5,000 lb boat without a whimper. It has over 100,000 miles now and I fully expect to take it past the 250,000 mile mark.
I'm not saying gas will outlast diesels. But most of the newer ones will make over 200,000 miles if treated half way decent.
If you tow for a living. Definitely go with diesel. If not, it is more a matter of personal preferences. I love my truck, but when I replace it, I will probably get a 2500 with the Hemi or a F-250 with the 5.4. Just my 3 cents worth (adjusted for inflation). I don't tow that much and I ending up doing a lot of idling.
10-06-2010, 04:34 PM
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I disagree with your disagreeing. I would expect most gas engines with moderate care to go at least 200,000.
Our 95 Safari van with a 4.3 was going strong when we went larger with our 98 Expedition, it had close to 190,000 miles and was not using any oil or showing any signs of quitting.
Our old 91 Explorer that our kids drove had a rough life. 3 teenage drivers. The 4.0 in it was running good at 184,000 and using no oil when the transfer case went out. I didn't want to buy a new transfer case so we gave it away.
I sold my Geo Prism with 300,000+ mi's on it. As far as I know the guy is still driving it. It did need new valve stem seals.
Our old 98 Expedition with a 5.4 has over 240,000 mi's on it now. We gave it to our daughter and Son-In-Law. They love it, it saw a lot of towing with our boat and is still going strong. When we towed down to LOTO this year we did only average about 9-10mpg. That was with the cruise set at 65-70mph, 6 people on board and a full Thule carrier on the roof.
We bought a 2006 Expedition with 5.4. It gets 15-17 average around town and will pull our 5,000 lb boat without a whimper. It has over 100,000 miles now and I fully expect to take it past the 250,000 mile mark.
I'm not saying gas will outlast diesels. But most of the newer ones will make over 200,000 miles if treated half way decent.
If you tow for a living. Definitely go with diesel. If not, it is more a matter of personal preferences. I love my truck, but when I replace it, I will probably get a 2500 with the Hemi or a F-250 with the 5.4. Just my 3 cents worth (adjusted for inflation). I don't tow that much and I ending up doing a lot of idling.
I would expect most gas engines with moderate care to go at least 200,000.Our 95 Safari van with a 4.3 was going strong when we went larger with our 98 Expedition, it had close to 190,000 miles and was not using any oil or showing any signs of quitting.
Our old 91 Explorer that our kids drove had a rough life. 3 teenage drivers. The 4.0 in it was running good at 184,000 and using no oil when the transfer case went out. I didn't want to buy a new transfer case so we gave it away.
I sold my Geo Prism with 300,000+ mi's on it. As far as I know the guy is still driving it. It did need new valve stem seals.
Our old 98 Expedition with a 5.4 has over 240,000 mi's on it now. We gave it to our daughter and Son-In-Law. They love it, it saw a lot of towing with our boat and is still going strong. When we towed down to LOTO this year we did only average about 9-10mpg. That was with the cruise set at 65-70mph, 6 people on board and a full Thule carrier on the roof.
We bought a 2006 Expedition with 5.4. It gets 15-17 average around town and will pull our 5,000 lb boat without a whimper. It has over 100,000 miles now and I fully expect to take it past the 250,000 mile mark.
I'm not saying gas will outlast diesels. But most of the newer ones will make over 200,000 miles if treated half way decent.
If you tow for a living. Definitely go with diesel. If not, it is more a matter of personal preferences. I love my truck, but when I replace it, I will probably get a 2500 with the Hemi or a F-250 with the 5.4. Just my 3 cents worth (adjusted for inflation). I don't tow that much and I ending up doing a lot of idling.
10-06-2010, 06:50 PM
#25
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My experience with gas engines is many will make it 200k without a major overhaul but start nickle and dimeing you around 125k.
Many Cummins engines will make it 200k or more without any engine problems at all.
Most fleet and government bean counters use 125k miles as replacement time.
They figure economically a new rig is cheaper than maintaining the old one.
Many Cummins engines will make it 200k or more without any engine problems at all.
Most fleet and government bean counters use 125k miles as replacement time.
They figure economically a new rig is cheaper than maintaining the old one.
10-06-2010, 07:07 PM
#26
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I don't think my family has ever gotten rid of a car that had less than 180k on it, we've never needed to rebuild an engine, and we never got rid of a car because the engine was bad - usually rust got 'em.
Here are the high milers that didn't get wrecked with the mileages when they were sold.
'84 Olds (307 V8) 248k, only internal work was a timing set around 150k.
'88 Ford (5.0 V8) 207k, engine never opened.
'93 Chrysler (3.3 V6) 192k, engine never opened.
'01 Dodge (3.3 V6) 216k, engine never opened.
Here are the high milers that didn't get wrecked with the mileages when they were sold.
'84 Olds (307 V8) 248k, only internal work was a timing set around 150k.
'88 Ford (5.0 V8) 207k, engine never opened.
'93 Chrysler (3.3 V6) 192k, engine never opened.
'01 Dodge (3.3 V6) 216k, engine never opened.
10-07-2010, 12:05 PM
#27
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The real difference in the two is the peripherals. Gas engine vehicles are usually designed for "Normal" use where as diesels are set up for heavy duty.
I figure since my truck sees mainly light hauling and no offroad my truck will outlast the butt it hauls around.
My gas vehicles are meticulously taken care of but usually around 150K water pumps, timing belts, alternators, hoses and emissions devices start acting up.
I figure since my truck sees mainly light hauling and no offroad my truck will outlast the butt it hauls around
.My gas vehicles are meticulously taken care of but usually around 150K water pumps, timing belts, alternators, hoses and emissions devices start acting up.
10-07-2010, 07:43 PM
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The real difference in the two is the peripherals. Gas engine vehicles are usually designed for "Normal" use where as diesels are set up for heavy duty.
I figure since my truck sees mainly light hauling and no offroad my truck will outlast the butt it hauls around.
My gas vehicles are meticulously taken care of but usually around 150K water pumps, timing belts, alternators, hoses and emissions devices start acting up.
I figure since my truck sees mainly light hauling and no offroad my truck will outlast the butt it hauls around
.My gas vehicles are meticulously taken care of but usually around 150K water pumps, timing belts, alternators, hoses and emissions devices start acting up.
The first evidence is increased fuel usage. The second is increased temps.
.
10-08-2010, 04:48 PM
#29
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My 7000lb'ish 2006 QC 4x4 SWB with 5.9L Cummins gets a solid 15.5-17.5 commuting
10-08-2010, 05:29 PM
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mpg
Well I might as well get in here too,I have a 98 12v that gets 24.5@ a steady 55mph,22.@65 ,20.5@75 & 12.5 w/a total weight of 16,480 towing.
It has around 199K & uses 1/2qt in 5K.
My 01 FL70 will av around 10 on the road w/a ISC weighing around18K
It has around 199K & uses 1/2qt in 5K.
My 01 FL70 will av around 10 on the road w/a ISC weighing around18K