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Discussion Starter · #1 ·
About to buy... best candidate to date is an '03 with the standard engine (250hp/460ftlb) and auto (47RE) with very low miles. I'd prefer to find an HO engine (305/555) with a stick or 48RE, but hate to let this one go (nice truck in great shape). I'll be towing some but the standard engine should handle what I'll be doing, with appropriate caution. Question is: will the standard engine give me better or worse mpg than the HO?
 

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actually that 03 you mentioned is a California engine judging by the power numbers, I'd stay away from it. You will get better mileage with the HO.
 

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i have the same motor in my truck and it does very well on fuel mileage and the build sheet says the truck was originally shipped from the factory to pa not cali
 
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Ca model is 235 hp I have one, runs fine tows a 11,000 lb boat or has a 4000lb camper on most times, 115,000 47re trans sill fine, my 2000 with stock auto is going on 375,000 miles no rebuild, all Dodge autos are good
 
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Discussion Starter · #6 · (Edited)
Ca model is 235 hp I have one, runs fine tows a 11,000 lb boat or has a 4000lb camper on most times, 115,000 47re trans sill fine, my 2000 with stock auto is going on 375,000 miles no rebuild, all Dodge autos are good
Good to know dragpipe , thanks, but a little thread cross-over too . In this thread I'm looking for feedback on the two engines' fuel economy, to see if I should go for the 'standard' rather than continuing to look for an HO, possibly losing a very low mileage truck in excellent condition. Since you're listening, what fuel mileage do you get with your engine... towing/highway(speed?)/local?
 

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Pappyrsg, you aren't going to get solid numbers in re MPG comparisons unless you can account for:

1] truck spec
2] climate
3] terrain
4] truck use (or, driver skill)

A 4WD, auto trans in hilly, chilly West Virginia will be considerably different than a 2WD, man trans on the Gulf Coast.

And, as very few keep records of all gallons/all miles the most important piece of information -- average mpg -- will be missing. Be sure to check engine hours and calculate average mph, also, as an average speed of above 27-mph is indicated for best fuel burn.

For all that, I'd choose the low miles truck. An auto trans + 4WD will chew money at or past 100k (where a 2WD + manual will go to 200k before needing similar work). I'd also avoid trucks with gooseneck hitches or evidence of a tuner installed.

My numbers in sig. Good luck.

.
 
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Discussion Starter · #9 · (Edited)
Thanks everyone... bought my Cummins!

Thanks everyone for your feedback. In this thread, I was looking for a fuel efficiency comparison between the 2003/2004first-half 'standard' and HO engines. The numbers and info I got, while not exactly an apples-to-apples comparison between those two engines in the same truck config running under the same conditions, gave me enough insight to know I should just go for the best deal and best condition I could find. I bought the 2003 2WD auto QCSB with the standard engine and only 61K miles. Drove it home from Phoenix yesterday getting 22mpg running at 70mph... a fairly flat drive with minimal wind impact but a 2500 feet gain in altitude to my home, and there was one crawling period (about 10 minutes) to get by an accident site. (And yes Slowmover I drive/accelerate/etc very conservatively... my wife had no trouble sticking with me in the Prius) That's a good start, given the exhaust (no Cat!) and intake are still both stock, which I plan to improve. I also plan to look into lowering and leveling an inch or two for better aerodynamics. There may be a chip/tune in the future too, but only after appropriate transmission improvements and then targeted at fuel economy... I think I already have plenty of power. She's been very well maintained (owned by a very experienced and diligent Dodge mechanic) and drove home like a new one... love the truck!
 

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Thanks everyone for your feedback. In this thread, I was looking for a fuel efficiency comparison between the 2003/2004first-half 'standard' and HO engines. The numbers and info I got, while not exactly an apples-to-apples comparison between those two engines in the same truck config running under the same conditions, gave me enough insight to know I should just go for the best deal and best condition I could find. I bought the 2003 2WD auto QCSB with the standard engine and only 61K miles. Drove it home from Phoenix yesterday getting 22mpg running at 70mph... a fairly flat drive with minimal wind impact but a 2500 feet gain in altitude to my home, and there was one crawling period (about 10 minutes) to get by an accident site. (And yes Slowmover I drive/accelerate/etc very conservatively... my wife had no trouble sticking with me in the Prius) That's a good start, given the exhaust (no Cat!) and intake are still both stock, which I plan to improve. I also plan to look into lowering and leveling an inch or two for better aerodynamics. There may be a chip/tune in the future too, but only after appropriate transmission improvements and then targeted at fuel economy... I think I already have plenty of power. She's been very well maintained (owned by a very experienced and diligent Dodge mechanic) and drove home like a new one... love the truck!
Drive by the tach not the speedo.
Best MPG is achieved by keeping the rev's at or BELOW 2k rpm.
 

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Discussion Starter · #11 ·
True rdefayette, keeping rpm's at or below 2000 is key to good mpg, and I do that at 70 (about 1950 rpm), will do it better at 65. But, really, you plan your trips and calculate your arrival time based on rpm... that's some wicked math dude! :rof Seriously, keeping the rpm below 2K and even lower to stay close to the torque peak is required for good mpg, but my trips are planned based on the clock, which is a lot easier to relate to in mph. Plus, driving too slow on some of today's highways can create a traffic hazard, so you do what you can. I'm just quoting mpg vs speed so others can see how I'm doing and compare it to their experience... by doing that, maybe we can all learn something new.
 

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True rdefayette, keeping rpm's at or below 2000 is key to good mpg, and I do that at 70 (about 1950 rpm), will do it better at 65. But, really, you plan your trips and calculate your arrival time based on rpm... that's some wicked math dude! :rof Seriously, keeping the rpm below 2K and even lower to stay close to the torque peak is required for good mpg, but my trips are planned based on the clock, which is a lot easier to relate to in mph. Plus, driving too slow on some of today's highways can create a traffic hazard, so you do what you can. I'm just quoting mpg vs speed so others can see how I'm doing and compare it to their experience... by doing that, maybe we can all learn something new.
only threw it out there 'cause you didn't mention rpm's.
wasn't sure what you were spinning so I didn't know if you could do better or worse.
If you know that 1950 rev's is 70 then the math gets a little easier. :)
 

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Pappyrsg, sounds like you're like just a few of us around here interested in the lowest fuel burn for the same work. Note there is no FE [fuel economy] subforum at CF. But there is a larger handful of DODGE CTD owners (and other truck brands) over at EcoModder.com.

" . . given the exhaust (no Cat!) and intake are still both stock, which I plan to improve. I also plan to look into lowering and leveling an inch or two for better aerodynamics. There may be a chip/tune in the future too, but only after appropriate transmission improvements and then targeted at fuel economy... I think I already have plenty of power. She's been very well maintained (owned by a very experienced and diligent Dodge mechanic) and drove home like a new one... love the truck!"

1] Stock exhaust is not really an impediment to highest FE. I have a ROKKTECH muffler (check specs on backpressure). The improved stock air filter is great, and a "Home Depot CAI" is worth a solid .5-mpg (if you live in a dust-free area. I sure don't, so I don't use one). The other intake restrictions (improved in following years) is found on '04.5 models where air turning vanes are present in the intake. An Airraid intake tube to replace the stock restriction "muffler" was a recent addition to mine, the feel is noticeably different.

2] THere are no lowering kits for the 2500/3500 2WD trucks. And "levelling" is contraindicated for FE. The FF/RR rake is beneficial.

3] SMARTY JR is the default tuner choice. I don't "beleive" in them (you WILL wear that trans faster), but the advance in timing is slightly beneficial.

4] Any auto trans would benefit from a spin-on filter (as the pan filter is really only a screen). I'd use SCHAEFEERS ATS fluid exclusively.


Agreed that the truck is already overpowered, We're a long way from a 1974 V8-440 Ddoge at 6-mpg towing.

See, on this site, rdefayettes bed cover. Aerolid design. A genuine aero improvment worth an easy 20%. Much more on this type at Ecomodder (where several builds are underway).

As to FE, anything above 60-mph is speeding. And NO truck handles worth beans above 65-mph; contraindicated for risk management. The range is 55-65 for best compromise. And, FWIW, I find it no problem to run the Interstate at 58-mph. It isn't difficult to find ways to ease the cretins around one (and they are, given their lack of three-second following distances in all instances). I find this an objection to be from those who never learned to use their mirrors, and that their daddies never taught them how to manage traffic.

So, we know the miles on your new truck. How many engine hours at present?

.

.
 
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Pappyrsg, sounds like you're like just a few of us around here interested in the lowest fuel burn for the same work. Note there is no FE [fuel economy] subforum at CF. But there is a larger handful of DODGE CTD owners (and other truck brands) over at EcoModder.com.

" . . given the exhaust (no Cat!) and intake are still both stock, which I plan to improve. I also plan to look into lowering and leveling an inch or two for better aerodynamics. There may be a chip/tune in the future too, but only after appropriate transmission improvements and then targeted at fuel economy... I think I already have plenty of power. She's been very well maintained (owned by a very experienced and diligent Dodge mechanic) and drove home like a new one... love the truck!"

1] Stock exhaust is not really an impediment to highest FE. The improved stock air filter is great, and a "Home Depot CAI" is worth a solid .5-mpg (if you live in a dust-free area. I sure don't, so I don't use one). The other intake restrictions (improved in following years) is found on '04.5 models where air turning vanes are present in the intake. An AFE intake tube to replace the stock restriction "muffler" was a recent addition to mine, the feel is noticeably different.

2] THere are no lowering kits for the 2500/3500 2WD trucks. And "levelling" is contraindicated for FE. The FF/RR rake is beneficial.

3] SMARTY JR is the default tuner choice. I don't "beleive" in them (you WILL wear that trans faster), but the advance in timing is slightly beneficial.

4] Any auto trans would benefit from a spin-on filter (as the pan filter is really only a screen). I'd use SCHAEFEERS ATS fluid exclusively.


Agreed that the truck is already overpowered, We're a long way from a 1974 V8-440 Ddoge at 6-mpg towing.

See, on this site, rdefayettes bed cover. Aerolid design. A genuine aero improvment worth an easy 20%. Much more on this type at Ecomodder (where several builds are underway).

As to FE, anything above 60-mph is speeding. And NO truck handles worth beans above 65-mph; contraindicated for risk management. The range is 55-65 for best compromise. And, FWIW, I find it no problem to run the Interstate at 58-mph. It isn't difficult to find ways to ease the cretins around one (and they are, given their lack of three-second following distances in all instances). I find this an objection to be from those who never learned to use their mirrors, and that their daddies never taught them how to manage traffic.

So, we know the miles on your new truck. How many engine hours at present?

.

.
what took so long my friend? thought you were going to miss out. :)
 

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My truck is a cali low horsepower 235HP engine and with the edge-ez set on level 2 I have gotten a best of calculated 21.8 mpg running with cruise set at 77 mph at 2200 rpm. I've made the same 500 mile run down the highway many times and the numbers are always the same 20.5 - 21.8 mpg. I guess I never run for true economy at about 60 mph. Like the poster prior to me it seems like my trips are time driven.
 

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I get the same as raceguy flat. 18-19 in the mountains. Speeds definitely vary here. 12-13 pulling a 9000lb travel trailer flat. I think I have a non Cali SO cummins. How do you tell if its a Cali edition or not?
 

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"Time driven" only means one left late. Leave earlier. On trips of under 300-miles there is no genuine "time savings" given not only lower FE, but accelerated tire and drivetrain wear (plus suspension, steering, etc). Having to brake, change lanes, re-accelerate, over-speed, etc, is the usual analysis of travelling higher speed, all of which is contraindicated for economy.

As with my comment about managing slower traffic, I notice that those who wish to travel faster are in a hurry to grip the TV channel changer on arrival. Where's the benefit? A little here, and a little there genuinely adds up over the course of a hundred thousand miles. Same for eliminating idle time.

Practices which extend the life of the vehicle are what true economy is about. The lowest cost to cover those extended miles is the icing on the cake. Longevity + safe practice does equal best fuel economy in reverse fashion: it dictates prudence. Which then pays cash money.

The big piece is that trucks roll over at highway speeds where cars will spin out. Pushing ones luck (risky habits) sooner or later is very bad juju. Wrong time, wrong place, what-have-you . . the excuses made about "accidents" is what is at stake. It is an emotional -- not rational -- problem to solve. Kick the teenager our of the drivers seat.

Besides, travelling at a lower speed is the low-hanging fruit. The beginners step. There is much more in terms of practice to doing the exact same work yet at a lower specific fuel consumption.

The OP is a travel trailer owner. As am I. And of the same type, though different brand (and far better than the average square white box in all matters of road performance, not simply longevity). The trade-off of using a truck as tow vehcile iwith this type (all aluminum, independent suspension, low COG, light relative weight) is that the TT can get through the slalom MUCH faster than can the truck solo (when behind a more capable tow vehicle than a truck). I really don't vary the way I drive whether solo or or towing. Makes for consistency. Better habits, IMO. Certainly makes for simplicity. Coming to a full emergency stop, TV & TT in a straight line is never quite easy even with the best TT type. From speeds of 60-mph or below it is a reasonable proposition. But not so from above 65. As the truck is the weak link, a VPP WD hitch is of real benefit, and indirectly of fuel economy (fewer steering corrections).

The TT I have was already 14-years old when the truck was brand-new. 24-years now. And it will be in service decades past the time the truck is retired. While I hope to have the truck at least 20-years past manufacture, it behooves me to keep it as new as possible, as long as possible. The all-around economy of a CTD can't be beat. And no new one will come close (costs are much higher inflation-adjusted, and longevity is unlikely to be as long). The cost per mile of operation is already higher, and will continue to go higher on new diesel trucks. So while fuel cpm could remain constant between 2013 and 2003 (barely), the other costs of ownership will be higher.

Put a vehicle into the longest-term context to show what should be done today. What habits are good to acquire -- skill development -- is to that end.

Fuel economy is just a measure of how well I am doing that. Same with tire and brake life as a measure of longest vehicle life. 120k on each of those is about right (180k for highway only).

The engine has an MTBO of 350k miles, or 10,000-hours. For my wallet there is qute a difference between achieving 300k or 400k before overhaul. Same for all other componentry. How long I will keep it, and how many miles it will acquire in that time is the first step for personal transportation budgeting. In some instances, one makes ones luck.

.
 
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Discussion Starter · #18 ·
More great info... and reopened an old debate?

First, thanks for the advice Slowmover, and everyone else for your input. One thing I think I missed in my posts, and I don't see in this particular post from you, is the consideration of return on investment. I'm not particularly interested in investing lots of money to save a little fuel. By that I mean, looking at a 2 mpg increase, which seems like about the best I can shoot for... IF my current combined average is 18 (that's optimistic, but I'm not yet sure what that number is), thus getting to 20, saves me $332 a year assuming $4 fuel (of course we're likely going higher in the next couple years) and 15000mi a year. Anyway, FE alone has its limits as far as cost justification. Your suggestion on the intake tube sounds like a reasonable near-term purchase... I take it you mean just the tube (part # 300-928), right? I was planning a muffler and air filter change for FE, but also thought it would help airflow in general thus keep EGT down. If not for FE, is that why did you switched to a ROKKTECH muffler? On the air filter, I've always found K&N to improve FE, not to mention cleanable for a few years... helped me get to 30mpg and beyond at 67mph in my (soon to be former) Jeep Liberty Diesel, with no chip/tune (although I did disable the EGR and re-route the 'breather' hose (aka slobber tube) away from the intake). OK, no lowering, and I'll look into the bed cover. Definitely not CAI... too dusty here too. As for the speed thing, I said my piece and will leave it at that... 65mph is probably where I'll be mostly, though I'll test at 60 to see if the FE is enough to pull me down there. On the transmission, where improvements have their own cost justification (avoid a failure), for towing's sake I was planning a deeper pan (though a little concerned about that hanging down below the cross-member), a Transgo kit, and monitoring the transmission temp via the OBD2 interface; and of course regular fluid changes (I'll check out SCHAEFEERS ATS, but I'm partial to Redline). I haven't been inside the trans pan yet, thought it would be like the setup on my Jeep trans (545RFE), which has an internal spin-off filter... so which one do you suggest, and how... cooling line intercept? The trans items have their own separate cost justification...hopefully avoiding failure. Oh, also planning a pre-filter fuel filter... probably the Cat 1-R0750 setup.
 

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Percentage changes to the average mpg is what FE is about. The mpg number, by itself, doesn't mean much (as you know). Nor the highs or lows per tank which are meaningless. An oft-stated average is 15 for the typical 4WD/auto, so at $4/gl + 15k annual miles so an increase to 18 would be 20% over typical. Over five years -- 60k miles -- that would be well over 650/gls of fuel. Given that economy is about longevity it's a winner on wear & tear, not just $2,700. The "money saved" is a stand-in, a representation of an overall larger savings on the vehicle. A fuel log (paper, app or online [I keep mine at EM]) that also records costs -- cpm -- as well a tab on average mph, is in all ways beneficial. Records are the first step, without them one is blowing smoke.

Agreed that spending to save is backwards. But there are some instances where premiums carry their own bonus. Very best tires are an example, where the best tread design/construction will cost more out the door. But may last 2-3 times as long as well as return a solid 2-mpg better. This is about the only easily documented FE change. FE is about small gains, and this is a big one (as we are speaking of changes to the average mpg).

Tire pressure is a place some truck owners get carried away. One should respect the OEM guidelines (max/min, as well as FF/RR bias). My truck, stock, was 6,860-lbs. Adjusted weight for many years was 7,340. Am now at 7,940-lbs on a 9k GVWR sticker. So tire pressure adjusted accordingly (50-psi Ff & 60-psi RR). Recommend you weigh yours for an adjusted empty weight (driver, full fuel + permanent supplies aboard) at a CAT Scale (nationwide locator online) as it also pertains to setting up a WD hitch. I did individual weights as well as axle totals (again, to verify future WD numbers) and am currenly within 40# all around. There is no benefit to higher than normal pressures (given a 5# margin) as one does not want to reduce tire patch per braking/handling (the yaw and rollover tendencies of pickups should always be scary). My first tires went to 120k miles with stock pressures.

Other examples of where to spend are absolutely perfect alignment, zero CAC leaks, zero brake drag, and zero steering wander. Zero means zero. And the numbers for verification. (This will also apply to the TT).

300-928: Yes. Am on the lookout for the 04.5 and later lower intake with turning vanes. These both are really highway, steady-state-only beneficial. But towing is where I'd like to bring my average from just over 15 to a solid 17-mpg with my 35' TT.

The ROKKTECH muffler was installed as it was quietest and lowest backpressure. The PO had installed an AEROTURBINE 4040 and without a resonator the drone was killing. Slid that forward and the new muffler behind it. So, even with two mufflers can still see 27-mpg, solo, on the Interstate some days. While there might be some advantage to an aftermarket system it won't be easily quantified. The 04.5 and later exhausts are slightly larger than our 03'-'04 trucks, so following the factory may be beneficial (if the cost is acceptable).

K&N is contraindicated for engine air intake cleanliness. The new, improved (4" deep) stock filter is good to 450 rwhp. I replace mine yearly, needed or not. Same for fuel filters. Use BALDWIN exclusively for the stock piece.

You already know the benefits of synthetic lubricants. Diesel_Dave, in his '08 6.7L has changed to a lightweight AMSOIL engine oil and reports higher mpg. He has the best numbers (and plots the most information) of anyone I know. In 2012 he saw a solid 40-mpg in his commute as a CUMMINS engineer. (The pertiment info on EM; and some on the forums here).

Yes, better fuel filtration than OEM is indicated (BOSCH wants more than DODGE provided). Injectors are far too expensive to ignore (and re-mans are unacceptable by all accounts). FASS, AIRDOG both provide fuel pump and filtration upgrades. See GENOS GARAGE for replacement lift pump (and carry one under back seat for the inevitable day short of upgrade). AH64ID has a long thread on best fuel filters worth bookmarking. Links from there on DIY.

As to the auto trans I don't have one. Thus am not up on details of where stock cooling might lack, nor do I have any links to DIY spin-on filtration (for these trucks, I had them for earlier vehicles). Obviously, a trans temp gauge (sump measurement of temp is industry standard). Look to DTT, ATS and other aftermarket suppliers as well as check out threads on the 47.

My other examples of "spendng to save" are a 4-piece grille block (as well as the MOPAR winter front) to aid faster engine warm-up and maintain higher engine temps in fall/winter/spring when solo (I posted details of use over on EM). The GENOS GARAGE bumper plug block heater cord (brings coolant to above 100F in 90-minutes); all of these a help to combat my short commute as well as aid engine longevity by greatly reduced warm-up times. And all were cheap. This spring has been cool, so we are just now reaching the point of constant A/C use. Thus I'll remove the lower portions of the grille block for greater cooling, but leave the upper as an aero aid (note the OEMS are about to start releasing auto grille shutters on trucks for the same effect). When I hook up the TT, off it comes.

The plan (as I see it) for most effective use of fuel is straightforward:

1] "Perfect" mechanical baseline. All maintenance, best supplies. Verified.

2] Smart Use: Combine all trips. The DHS, in a study released a couple of years ago found that 90% of Americans drove to 90% of the same places 90% of the time. Use MAPQUEST for "Best Order Routing" (avoid left turns, etc). IOW, do the same work, but greatly reduce the number of annual miles, not just cold starts.

3] Smart Driving: Drive the remaining annual miles at a conciously higher level of skill (much more on EM). If I can move my town mpg from 18 to 23 by this, so can anyone. I'm too lazy to do better than an average 19-mpg overall, but the establishment of better habits with an eye towards safety in all aspects is what motivates me.

Most would be satisified with the 18-mpg I saw in town. But by conciously working to get to the 23-mpg I was able to achieve over 1,100-miles had I continued that for a full year (the annual fuel budget at stake) I would have completely underwritten 5,000-miles of TT towing. A pretty much "free" set of vacations, in other words . . . find what works for you is my recommendation.

My mantra is this:

Safe, efficient use to ensure the most work over the longest life and lowest cost with the highest reliability.

Let me again extend an invite to join over at both EM and AIR. Best practice gives best results. Extended, in-depth, at both on what those practices should be (and what equipment or other is actually beneficial).

YMMV

.
 
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