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Diesel vs. Gasoline

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Comments

  • dodgeramdodgeram Member Posts: 202
    Not really, remember dodge has a flat powerband, while the fords curves back down, so dodge would pull ahead in the steeper grade.
  • stanfordstanford Member Posts: 606
    That's fairly invalid. Ford's powerband is higher than Dodge's peak. If the Dodge wasn't limited for the transmission, it would peak to about the same amount.
  • dodgeramdodgeram Member Posts: 202
    Heres more proof. In order for a ford to climb steeper hills the engine has to rev alot higher, meaning the transmission has to kick down and the engine rpms raise to what ever there rpm range is I think around 2400rpm's. This means reving higher, means shorter enginge life and milage is going to lower. The dodge engine won't be reving that high because 90% of it's total power is at 1600rpm so enless its a very very steep hill the dodge will climb it more easily without overworking the engine and doing it with better fuel milage.
  • stanfordstanford Member Posts: 606
    Actually, the Ford and Dodge curves are very similar if you ignore the Ford peak. What makes you think that the Ford would need to downshift to get up the hill? I've driven both, and they're both capable as the study points out. I don't consider a 4' difference proof of anything, no matter who's ahead, that's less than I'd expect them to vary if they ran 3 tests and averaged the numbers.

    BTW: The fact that Dodge makes 90% of its total power at 1600rpm is irrelevant here. If it wasn't limited and got 500lb.ft like the Powerstroke that percentage would be lower, more like 80%. Would this mean that it got less power? Of course not.
  • tmd01tmd01 Member Posts: 23
    What surprises me here is that most of the people buying the bigger trucks are not concerned with fuel mileage. Nor does there seem to be much concern over engine life, although I do see the occasional comment. Initially I liked the SD's because of their quickness. And...I thought they were getting pretty good fuel usage. The bottom line I seem to be getting here is that the V-10's have plenty of power, but forget fuel mileage. The 454 is about the same, but less power. I have access to a 454 and a PSD and PSD outruns the 454 in speed and milage. Both trucks are geared about the same and have auto trans. The diesel battle seems to be between choosing a hot rod truck or a chugger truck. I like the hot rod, but if I have to pay a penalty in fuel milage and engine longevity, I may have to choose the chugger. I might get there a few minutes later, But I will get there. Now if the factory will only produce a reliable torque convertor and auto tranny....
  • stanfordstanford Member Posts: 606
    Actually, the savings only pays for the diesel after about 100K (see earlier in this and the Gas Mileage topic for all the sordid debate), at which time some of these newer high-tech diesels can start to hit you if they need repairs (injectors, for instance). This topic has been somewhat beaten to death... I think most folks agreed that they came out pretty much even if you're not doing almost all OTR driving.
  • mroffshoremroffshore Member Posts: 148
    tmd01,

    I choose the PSD for mileage and longevity. I have the mpg 17+ around town and 20-21 highway. Hopefully I'll get the other also!

    Stanford,

    I'm hoping to maybe come out a little ahead after 100,000 miles because of the good mileage I'm getting with the PSD. Now the variables will be fuel cost of gas and diesel. I originally thought that gas would stay higher then diesel. So I'm going to out smart the oil companies and buy the PSD for that good milage.HAHA! Oh well I still think I made the right decision. I do not expect to see low fuel prices too much longer but then again who knows!

    Mroffshore
  • stanfordstanford Member Posts: 606
    A good point. And even after all the logic I put behind my decision -- I will admit that I do miss my diesel a lot. You really can't get that feel from a gas engine.
  • rgjd401rgjd401 Member Posts: 5
    What kind of MPG are the V10s getting. I dont see much on that???
  • stanfordstanford Member Posts: 606
    Check the 'gas mileage' topic. What sort of application?
  • bass1bass1 Member Posts: 2
    Could anyone tell me what mileage I could expect to get fron f250 PSD 2WD 6speed manual with a 3:73 rear axle. How would this compare to the Dodge Cummins 6speed manual.Iam looking at both trucks and would apreicate all the input I can get
  • mharde2mharde2 Member Posts: 278
    With the cummins you can expect 15-16 city and 20-21 hwy. With the PSD 1-2 mpg less.
  • dodgeramdodgeram Member Posts: 202
    Actully, dodge isn't going to offer a six speed manual transmission, for the current Ram trucks.
    But, in the next month or two, dodge will have a six speed, AUTOMATIC BY ALLISION. It hasn't been confirmed yet but it's almost a done deal. check out www.car-truck.com chrysler edition, for more details.
  • lex2lex2 Member Posts: 1
    six speed man order code DEE $340 ava now
  • stanfordstanford Member Posts: 606
    The Cummins is available with a 3.55:1 axle, the PSD only drops to 3.73:1. The PSD should get ~20mpg in that combo from folk round here who have one -- expect ~16mpg city as well.
  • mroffshoremroffshore Member Posts: 148
    bassl,

    I can confirm what stanford said although I am getting a little better around town, 17mpg. I live in a rural area but I have some stopping and starting. I also have a 4x4 crew and that is some extra weight.

    Mroffshore
  • bubba19bubba19 Member Posts: 16
    Hey offshore,

    I just read your post, and I would like to know what kind of truck you have. I am looking at the F-250 4x4 diesel. I have the F-150 now, and you are getting better fuel mileage than I am, so if the Ford F-250 can achieve the same as your truck I will have the best all around truck.

    Thanks.
  • mroffshoremroffshore Member Posts: 148
    bubbal9,

    I have the f250,crew, auto, 3.73 rear, 8ft bed, 4x4, lariat trim, camp and tow pkg. I also added a fiberglass cap by century. The cap is flush with the roof.

    Now I will say this, with each passing tank my mileage improved through 4,000 miles or so. I also noticed a slight drop in mileage due to winter diesel. But I can honestly say I get a solid 16.5-17 mpg around town and 20-21 on the highway sometimes a little better on the highway. Quit frankly I'm amazed at the mileage I'm getting. That truck is heavy for sure. Now I can honestly say it paid to get the diesel. That is totally my opinion. I have listened to and discussed since March on this very site all the pros and cons. For me, the diesel will pay for itself with this mileage.

    Can my engine be that much better tuned then others? Who knows, I just assumed everyone who bought the power stroke, enjoyed the same good MPG
    that I am getting. I'm sure there are other variables but all and all everyone should be close to my mileage. There is probably a problem if there are gross differences.

    Hope this helps,

    Mroffshore
  • KCRamKCRam Member Posts: 3,516
    stanford,

    The Ram is 3.54 and the Ford is 3.73, but the effective ratios are dead equal. Why? The Ford has taller tires - 235/85 and 265/75 over the Dodge's 215/85 and 245/75. Likewise, the Ram's 4.10 and Ford's 4.30 have the same effective ratio. The Ford 4.10 has no Dodge equal - Dodge would have to offer a 3.90 to match it.
  • tnt2tnt2 Member Posts: 115
    kcram
    Ford doesn't offer the 4.30 with the powerstroke. The 4.30 is available on the v-10. Also, the effective ratios may be the same, but there is the difference in the unhung weight of larger tires and the hung weight of each truck.

    mroffshore

    I agree. F350 CC 4x4 4.10 auto DRW LWB Lariat trim with cab high fiberglass topper, 14 local 17-18 highway. These are current winter driving conditions.
  • RichRich Member Posts: 128
    First, y'all are doing better int he mileage department than I. It's probably my 87 pound right foot.

    The other evening I received a call from a 'survey taker'. The survey taker was obviously following a menu on a computer screen. The conversation went something like this.

    Hello, I'm taking a survey. May I have a few minutes of your time?
    Sure.
    May I speak to a licensed driver over the age of 18?
    Speaking.
    What make of vehicle do you own?
    Ford.
    What year?
    1999.
    What model?
    F-250.
    How often do you buy gasoline?
    Never.
    (Pause, much furious clicking on the keyboard.)
    Hello, I'm taking a .... er.....
    May I speak to another licensed driver over the age of 18?
    Does this person have to purchase gasoline?
    (Finally out of the computer menu script.) Yes, of course, this survey is being taken is funded by a major oil company.
    Well, nobody in this house purchases gasoline.
    (Very frustrated now.) How can you own vehicles and drive without buying gas?
    All the vehicles are diesel.
    CLICK

    I still chuckle thinking about it.
    Rich
  • KCRamKCRam Member Posts: 3,516
    Rich,

    my day job is programming those computer surveys :) - don't worry, I never take offense to people taking shots at it.

    Since I have a Cummins, believe me, I would have pointed that out to the client before finishing the program. I would have asked them either to make the question "fuel" over "gasoline", or add a terminate point if they did not want diesel owners in the survey. But that's from a decade of being in market research...

    That furious clicking, by the way, was the interviewer backing up to the beginning because they had no idea what to do with you :)
  • mroffshoremroffshore Member Posts: 148
    Rich,
    I love it!

    Mroffshore
  • swampy2swampy2 Member Posts: 1
    Rich.
    I almost fell out of my chair, about the survey. I'm new to the group and was very pleased to see the web page from car and truck about the Allison Transmission for the Dodge. I have plans on getting a 25oo Lb to haul a trailer and have been thinking cummins but have heard bad rumors about the tranny. so maybe by the time I,m ready they will have the allison out. Thanks for all the info. really enjoyed it
    Bill
    m
  • tom60tom60 Member Posts: 10
    I am new to this site and found it very interesting. How come no one mentions the 5.4 for the F-250. Is it underpowered. Seriously thinking about the 7.3L diesel but I have concerns about the Michigan winters. I have a cabin in the north woods with no electric. Should I be concerned about starting? I drive almost 600 miles round trip couple times a month so I think the diesel could save me fuel costs. Comments greatly appreciated since I have to make up my mind by the middle of March if I am going to get a diesel so I can have it in October when my lease runs out on my 98 F-150. Thanks
  • quadrunner500quadrunner500 Member Posts: 2,721
    tom60,
    If you have something that could use a strong diesel engine to pull it, your decision would be much easier. Your mileage is not that high, and some full size V8 gas engine 4x4 trucks are getting 18 mpg on the highway. Also depends on the price of diesel in your area.

    As for the 5.4 engine for the F250, the problem seems to be that Ford chose to stick a higher output version in the F150, leaving the 5.4 in the F250 with a lower output design. That takes a bit of luster off the shine, but is probably a good practical choice.
  • stanfordstanford Member Posts: 606
    The other point is that the 6.8l is effectively the same price as the 5.4l and is posting better mileage while towing a heavy load.

    If you don't need to tow, then the fuel savings of the diesel are pretty much offset by the extra initial cost. If you keep your truck until it has 100K miles or so, the diesel will start really saving you money at the pump (watch out if it ever needs a repair though).

    Since you mentioned that you were getting rid of your last vehicle after 1-2 years, a diesel might not be best for you. The 5.4l works well in the F250, the 6.8l gives you a bit more power and better towing manners, offset by higher unloaded fuel costs. Personally, I'd go with the 6.8l and 3.73:1 gears, but you know your situation best.
  • jcs3rdjcs3rd Member Posts: 2
    In the next month I will buy a new diesel pickup. I'm in a quandary between the Ram 2500HD and the F250 Super Duty. With either I would like a five speed. I'm leaning toward the Dodge, basically because I like the looks and feel that for such a pricey option, the Cummins maybe is a superior motor to the Ford's diesel, whoever makes it. Can someone guide me? Also, what mileage should I expect unloaded? If I rarely go offroad, is the 4x4 worth it? I've kept my Saab for 10 years and plenty of repair costs and plan to keep the truck for the same amount of time. Thanks. John
  • markbuckmarkbuck Member Posts: 1,021
    Two wheel drive pickups trucks are quite poor on the ice and snow relative to other types of vehicles, but I usually prefer them due to simplicity, fuel economy, ride, lower repair costs.... Make sure you go for a limited slip though.

    Having owned a ford diesel for 10 years, I'd buy the cummins dodge motor if I was gonna keep it a long time. If I wasn't going diesel, I would go with a SD or a Silverado.
  • jcs3rdjcs3rd Member Posts: 2
    I live in Houston, however there is a remote possibility I could be relocating back east to a colder and snowier climate. I like the idea of longevity in a diesel, though I realize that there other parts of the power plant not necessarily so long-lived (injectors, fuel pumps, etc.) Most of all, to be honest, I like the throbbing note of the diesel. I would occasionally be hauling a 5,000 lb. sailboat. But, for the most part, this vehicle would be used for the commute and trips around town. I know that the diesel probably isn't the most logical choice for my needs...I just like it.
  • KCRamKCRam Member Posts: 3,516
    jcs,

    Be aware that the Ford F250 with the Powerstroke only comes with a six-speed manual. The Dodge comes with the 5 speedd; the 6 speed is now on hold until the 2000 model year - any existing orders for the 6 speed that were already accepted by Dodge will be built as 1999s, but that's all.

    As for fuel economy, if you go with the 3.54 axle on the Dodge or the 3.73 on the Ford, you will easily achieve low 20s with either truck, provided you can keep you right foot in check :)

    Comparatively speaking, both engines will do the job. The Cummins may cost a little less in maintenance, since there are two less cylinders to work with, and the Navistar HEUI injection system may be more expensive to maintain or repair down the road.

    It will basically come down to the seat-of-the-pants on the decision.
  • quadrunner500quadrunner500 Member Posts: 2,721
    Kcram didn't mention automatic transmissions, but for living in Houston, shifting could get to be a pain at rush hour. When kcram said you can only get a six speed manual in the Ford, I think he was comparing that to Dodge where there is or was a 5 or 6 speed manual choice. Dodge also has an automatic, as I believe Ford must?? I would be inclined towards Ford's automatic, or towards Dodge's manual (5 or 6 spd). Either one is a nice truck. If I could be sure I was staying in a place like Houston, I would certainly avoid 4 wheel drive. No sense in taking chances flooding out transfer cases and front differentials, if you didn't need them to begin with. You'll have a better ride too. But if I was to buy, I don't have that option and I would require 4x4 for winters and un-improved roads. The styling of the SuperDuty is definitely growing on me, though I still prefer the plush interior appointments of the Ram, especially if you are treated to camel/tan leather. The SuperDuty is a little too tall for some garages if that's a consideration.
  • markbuckmarkbuck Member Posts: 1,021
    Still mechanical? How frequent does one adjust valve lash? If you take it to a dealer, how much does it cost.
  • KCRamKCRam Member Posts: 3,516
    quad,

    I didn't mention the automatics to jcs because he did mention he wanted the manual in post #292. I agree the Ford 4R100 is probably the best of the bunch, but it's also brand new (only 1 full year old), so its long-term durability is still an unknown. The Allison 1000 6 speed automatic that will be going into Cummins-powered Dodge Rams has also been pushed to the summer - it will probably see duty in the first of the 2000s.

    markbuck,

    The valva lash on the 24v has been extended to 150,000 miles. The average buyer will probably never do it unless they want to. By comparison, the 12v was at 24K, then every 48K after that.

    A factory Cummins shop charges about $100-$150, a Dodge dealer is about $200-$250.
  • mccdon1mccdon1 Member Posts: 32
    How much will the Allison 6 speed auto cost when it becomes available? Any guesses?

    Thanks,
    Mac
  • RichRich Member Posts: 128
    With the recent merger of C & MB, I seriously doubt the Allison will ever appear in a Ram. More than likely it'll be a MB Truck trans.
    Rich
  • KCRamKCRam Member Posts: 3,516
    mccdon,

    considering the 47RE is around a grand, I would expect the Allison to cost anywhere from $1200 to $1500. For the durability, I'd pay it in a heartbeat.
  • weswes Member Posts: 5
    I am considering buying a gmc diesel in a suburban. I have read through quite a few of the comments and with the exception of a few such as the guy who had a lemon, I'm still trying to figure out why the gmc diesel is so bad. I have heard the report of the injector pump, but other than that, will the engine last as long as the ford or dodge? I don't plan to do a lot of pulling other than a two horse trailer from time to time and long trips several times a year. I like the idea of a diesel for fuel economy and torque, but I don't want a lemon that will burn out at 50,000 miles. This thing is to expensive!
    I would appreciate any feedback. I will be making a purchase within a couple of weeks.
  • rkquinnrkquinn Member Posts: 11
    I'm retiring. My wife and I would like to tour the country. We're considering buying a new Ford F-350 4x4 SRW Super Duty extended cab longbed pickup and a camper. The camper will weigh between 3,400 and 3,600 pounds with options and fluids. We plan to tow a motorcycle on a trailer. We'd like to avoid a dually, because our garage opening is only 8.5 inches wider than the dually's rear end. We've heard 'horror stories' about the Triton V10 getting only 9-10 MPG, on the highway and UNLOADED. The Powerstroke offers much better fuel economy. However, if I get the Powerstroke engine (additional 635 pounds) and 4x4 (additional 445 pounds), my cargo carrying capacity will be significantly reduced. Ford says that the maximum cargo weight of the F-350 Superduty with an 8' box, 4x4 and diesel, is only 2,922 pounds. Questions: Can anyone tell me what gas mileage they are getting with the V10? Can the F-350 be 'strengthened' with any of Ford's 'packages' to allow us to have the diesel, 4x4 and camper? Any suggestions would be much appreciated. THANKS!
  • stanfordstanford Member Posts: 606
    rkquinn: Usually one conference is enough :-) See replies in the Ford Super Duty conference.
  • dodgeramdodgeram Member Posts: 202
    Wes,

    If the gm diesel was a good motor, Gm wouldn't be spending all that money, on a all new one, especially when they have to get it from someone else. They know there diesels aren't the greatest. if you buy one you probably will have the common problems, injector pump, valves sticking, and other things that are more rare. If you wan to take a chance go ahead, but cummins is a way more superior to the 6.5. You don't hear to many bad things about the cummins. And when they get that allison 6spd auto in there, it's unstoppable. Think about it, You got rams great looks, one of the best trannies, and the legendary cummins, under the hood. What other truck offers that kind of power,quality, and strength. That why Im buying one when they get the new tranny.
  • bigfur1bigfur1 Member Posts: 34
    Dodgeram, keep in mind wes was looking at a suburban not a truck. I think that dodge should make a full size SUV with the cummins option.
  • weswes Member Posts: 5
    dodgeram, bigfur 1 is right, I need the suburban for the family. If I was in the market for a truck, the dodge with the cummins is the way I would probably go, even though I have been a Ford lover for the past 20 years. However, my fords have all been gas engines. Dodgeram, the things you mentioned; the injector pump, valves sticking, etc., how often do these things occur? Is it every 20,000 miles or so or does it vary? I have asked these questions on the SUV page, but no response. It seems you truck guys have more experience with the diesels. Thanks for the responses.
  • cdeancdean Member Posts: 1,110
    GM diesels had lots of software problems from '94 to '96. Mechanical problems weren't that common, other than the common fuel pump replacement between 100,000 and 150,000, maybe more if you're lucky. The newer ones don't have anymore software bugs, and haven't heard of any more frequent problems, as was occuring a couple of years ago. I think the engine is now reliable, and would be a nice motor for a surbaban that pulls a lot, or sees long highway miles. See if you can get a mileage rating on the vehicle. the gasoline surbabans are getting around 15 mpg. Your diesel would have to do around 18,19,or 20 mpg to make the extra 3000 dollars worth it. I don't think the diesel suburbans are getting that much mileage. The power is pretty good on the GM diesels especially for a suburban, 440 ftlbs, 230 hp, would easily pull more than the vehicle is rated for. I'd really check, though, to make sure its economically viable.
  • RichRich Member Posts: 128
    Wes,
    I had always been 'A Chevy Man'. I wanted a diesel in a Chevy wagon. By the time to trade was right, the word was out and the diesel was wrong!

    That was the past and too many years ago. The problem and the perception still exists. Now GM builds a significantly lower percentage of the world's vehicles. About the time GM converted their first automotive application diesel they also started this platform thing. A Chevy used to be a Chevy, an Olds used to be a Olds, etc. Now everything is a Chevy. Oh, the others have slightly different crinkles in the sheet metal, different badges, additional sound proofing and a list of different options. Other manufactures do about the same thing, some not as blatant as others but most build a single platform across divisions.

    With diesel engines, you design for a diesel from the first eraser put to paper. GM knew better but started with a gas engine block and converted it to diesel. It didn't work. Engines were typically replaced under warranty every 40K miles or so. There were numerous recalls. One of the more infamous recalls was to place a sophisticated washer under an elongated head bolt to prevent the heads from cracking. (Didn't work well.)

    All of this did not do the diesel engine in any car any good in the US. For a while, MB even stopped importing them. VW too. Every manufacturer was forced to go to a multi year 100K warranty on the power train.

    Over the years GM diesels have achieved near gasoline like reliability. Other manufacturers' diesel engines have achieved reliability in their light duty engines that approaches heavy duty engines. (The Cummins is a really good example of this. The Navistar is almost as good.)

    I really liked the suburban but I didn't like the relability of the diesel. Dealers were discouraging about ordering a diesel. Most would order a gasoline version for $100 while it was $2000 to order a diesel version. I would have bought an Expedition but no diesel was available. I settled for a super duty F-250 with 7.3L and no regrets. (I still like my neighbors suburban, though.)

    If you like the suburban get it! Get the biggest gasoline engine and low ratio (Economy) rear end. Your mileage won't be too bad. If you are REALLY going to tow a lot, have an auxiliary gear installed in your transmission. (US Gear is one brand.) I know that if I were going to tow a lot, I would avoid the GM diesel. There are many other brands that I just trust MUCH MUCH more.

    Rich
  • weswes Member Posts: 5
    Cdean & Rich

    Thanks for the comments. That is the type of information I have been looking for.

    I was aware of the past problems with the GM diesel being built from a gasoline block, but I was pretty sure they had dropped that bad idea several years ago. The suburban I am looking at is a 99 and I think from what I am hearing on this conference is the stigma of old is still around with GM regarding their diesels.

    Anymore comments will be appreciated. I still am not sure which way I will go. It may boil down to the best deal I can get on either the gas or the diesel. Will let you know what I decide to do.

    Thanks again, this has been real helpful.
  • stanfordstanford Member Posts: 606
    The gasoline suburbans are getting 15 mpg? Funny, every magazine article I've read and owner I've talked to is reporting more like 10-12.
  • cdeancdean Member Posts: 1,110
    our family's suburban gets 13 town 16-17 highway, and generally 15 with the mix. We got 18 mpg doing 75 mph, hauling 6 people and a tiny trailer from Austin to Steamboat, Colorado.

    i've never read a magazine report of a suburban, but i know LOTS of folks that own them, and 14-15 is the average report. i've never thought about it, thats just what everyone says. the only folks getting 10 mpg gallon are the ones with the 3/4 ton and 454.

    maybe the report you read had a low rear end ratio in it.
  • cdeancdean Member Posts: 1,110
    it was a really long run without stopping, in very cold dry air. like i said normal 30 mile highway drives yield about 15.
  • RichRich Member Posts: 128
    Let me preface this with, this information is about 10 years old. Also I'm not sure of the basic changes in the GM light duty diesel line since then. (I think that it was 6.2 evolving into a 6.5. Some of you GM guys, please correct me.)

    A friend had a '84 F-250 with the 6.9 L. His father had a GM pickup with a diesel. I think it was newer than the Ford. I was told this about '87 or '88. The statement was that the GM gave 30%-40% better mileage than the Ford when empty. When towing the Ford gave about 30% better mileage. Both vehicles towed the same horse trailer with the same horses.

    I don't know much more details than that. I do know that the son got tickets on the Kansas turnpike for speeding. (When the limit was posted at 80 MPH.) When he came to town it was always gas to the floor or wheels almost locked up. A true binary vehicle operator.

    Rich
This discussion has been closed.