What to watch for in 03-04's

[Prairie Dog]

Welcome SpeedBeef. Your mileage sounds about right of an 06. For some reason they just don't get the mileage of the older trucks. Maybe it's the 3rd injection event, I don't know. But your MPG is the same as my buddies 06 with 17k on it.

 

[Mark31]

SpeedBeef, you are going to get better answers than I'm can give, but since no one has jumped in yet, here goes. My 04 should should get slightly better mileage than your 06,but I can't imagine mine using that much fuel. I'm going to get 600 mi out of this tank, and 42 miles of that was with a 24,000 gross load. Since you are new to Cummins diesels, I'm going to take for granted that you are new to all diesels. Check your air filter. You can't do any better than the newer stock Mopar filter. If you have larger tires and/or aggressive tread, that will cut you. With my stock size Michelin MS 2 tires, I run about 55 lbs in the front and 45 in the rear empty. A 1000 pounds of gear or what have you will also cost mpgs. Watch your idling time. Cool it in neutral for a minute, 3-4 if loaded or running harder, then cut it off. Since I have an old S 15 GMC for a beater, I try not to crank the Cummins up unless I have to go ten miles. It takes a while to warm up 7 gallons of water/antifreeze and 12 quarts of oil. Some of the internal pollution control stuff started on the 04. 5 trucks, so almost immediately the oil will be looking black. FOR ME, if I couldn't get at least in the 15 range, I would be looking for a "tried and true" Cummins shop. Mark

 

[SpeedBeef]

Thanks for the replies. My truck is all stock, with the exception of a Magnaflow muffler and a new stainless tailpipe (stock 4" size). My tires are the stock size and are aired according to the pressure label on the sidewall (max). The truck is an auto, I don't know what my gear ratio (rear) is. I just topped it off, 11. 0 gallons to go 121. 2 miles, although none of this driving was highway. I will check my air filter again, I have a Dodge dealership about 2 miles away, so getting a Mopar filter is not a problem.

 

[rscurtis]

The Rokktech crank sensor may give you some benefit. A friend had an early '04. 5, it really drank fuel, although he does have a big right foot. Local driving was in the 11's (overhead display), and a steady state 50 MPH was only about 18 MPG- not very impressive at all. The reflash available for that vintage and the modified sensor made a big difference.

 

[SpeedBeef]

The Rokktech crank sensor may give you some benefit. A friend had an early '04. 5, it really drank fuel, although he does have a big right foot. Local driving was in the 11's (overhead display), and a steady state 50 MPH was only about 18 MPG- not very impressive at all. The reflash available for that vintage and the modified sensor made a big difference.

I was driving to the Dodge dealer to get a new air filter when I head a slight groaning noise coming from the right rear. Turns out that I had a piston stuck and dragging on that caliper. It was freed up/cleaned up/lubricated. I'm guessing that driving with one of the brakes partially on had a negative effect on my fuel mileage. I will see if the brake work helps, and replace the caliper if necessary. If that has no effect, I'll try something else. Diesel is currently 3. 99/gallon here, so I'd like to stretch the fuel as far as I can. Fortunately, I don't have to drive my truck daily (I just want to).

 

[Zuber]

This can be either an injector problem, or on early 2003 trucks there was a TSB for a clutch knocking noise. In the case of the injector, the problem can be fatal. In the case of the clutch, it's harmless but some find it annoying. The way to tell the difference is the clutch noise disappears when you depress the clutch.



rbattelle can you elaborate a little more on this clutch noise? i have an 03 nv4500 and when the clutch is out it sounds like something is rattling. the noise disappears when the clutch is depressed. how can you tell its not a throwout bearing or something else? thanks

 

[CBlack]

11-12mpg in town sounds low. I know guys with the same truck getting 16-17 in town and 20-22mpg highway.

I'm getting 17mpg in town with my 6. 7.

 

[RVTRKN]

The only problem you will run into, finding a low mileage 04. 5/05 MY with the NV5600 trany, by far the best of the CTD's.

 

[Mark31]

Thanks for the replies. My truck is all stock, with the exception of a Magnaflow muffler and a new stainless tailpipe (stock 4" size). My tires are the stock size and are aired according to the pressure label on the sidewall (max). The truck is an auto, I don't know what my gear ratio (rear) is. I just topped it off, 11. 0 gallons to go 121. 2 miles, although none of this driving was highway. I will check my air filter again, I have a Dodge dealership about 2 miles away, so getting a Mopar filter is not a problem.

Speedy, you aren't doing yourself or your truck any good running so much air in your tires. You're just beating up your gizzard, and your truck's ball joints and suspension and every thing in or on the truck is taking an unnecessary pounding. The figures on the door are for max load. A sheet came with my truck showing the load carrying capacity of the tires down to near 40 psi. Try my 55-45 psi cold. Might save you from jarring a filling out of a tooth! Let us know if fixing the dragging brake helps your mpg. Mark

 

[TCDiesel]

I took a chance at buying the first year of a redesign but it turns out I (arguable) got the best year ever.

I did the same... 03/04 will go down in history as the best and most mileage CR. Chris took in on repairs idler/TENSIONER/belt. The mileage 687k (2003). Chris ASK for history form customer, 3 MTs-Chlts,2 water pumps,3 sets of Injectors and a few wear parts ,common suspension, Customer stated uses 1QT of oil every 5k or so. Hard to believe the Idler and Tensioner were Factory.

 

[rscurtis]

The '03 wasn't exactly the first year. The third generation body started life in '02 for the 1500 series, and the CR engine was used in Europe several years before it saw life here.

 

[SpeedBeef]

Speedy, you aren't doing yourself or your truck any good running so much air in your tires. You're just beating up your gizzard, and your truck's ball joints and suspension and every thing in or on the truck is taking an unnecessary pounding. The figures on the door are for max load. A sheet came with my truck showing the load carrying capacity of the tires down to near 40 psi. Try my 55-45 psi cold. Might save you from jarring a filling out of a tooth! Let us know if fixing the dragging brake helps your mpg. Mark

I did take my tires down to 55/45 F/R cold, and my mileage seems to have improved since the brake caliper was serviced (no more dragging). I will hand calculate once I drop down to 1/2 tank. Seat of the pants and eye on the gauge says it has improved .

 

[SpeedBeef]

Ok, tires are 55/45, brake is no longer dragging. Fresh oil change and new fuel filter. If I drive very conservatively, I get 12mpg around home (not much if any highway). I did install a new Mopar air filter as well. Anything else I can do? Or are 06 5. 9s just thirsty?

 

[Prairie Dog]

The '03 wasn't exactly the first year. The third generation body started life in '02 for the 1500 series, and the CR engine was used in Europe several years before it saw life here.

Mpst of us here are familiar with Dodge history but for us here at the TDR, life kinda revolves around the CTD so the 1/2 tons don't really enter into things (usually). So yes, 2003 was the first year of 3rd gen CTD heavy duty trucks, sold in the USA, if you wan't me to be more specific.

Cheers,

Scotty

 

[Mark31]

Speedy, other things that cross my mind are: 1. Your trip length. If you are just going to do 15 minute runs and not warm up all the way, you've got your truck doing something not really in its design objectives. Diesels are kinda like the Eveready Bunny--they like to keep going and going and going! I think I would plug in the block heater more if I was short tripping. 2. If your transmission isn't locking up the torque converter, that will take more fuel. 3. If you have a 4. 10 rear end instead of a 3. 73, that's going to hurt. At 70 mph, you should be running about 2000 rpm with a 3. 73. 4. Have they started "winterizing" fuel up there yet? Some here on TDR say it cuts their mileage more than a little. 5. Dealers have a way of pouring sour milk on my Cheerios, so it even hurts to say this: One of the earlier posters mentioned a reflash for the 06 trucks. If you can find a dealer you have any confidence in, you might check to see if this has been done to your ride. (Whew! That hurt even to say go on a dealer's yard!) Three (?) years ago, our Baptist Disaster Relief Team went to Kentucky after the ice storms. I pulled a fairly tall 14 cargo trailer and a friend pulled his Bobcat with his 06 dually. He had more weight, but I had more wind drag. I think the 2 trucks used the same amount of fuel on the trip. Hope you can get some relief! Mark

 

[SpeedBeef]

My truck has been used mostly on short trips recently, a lot of the time it never gets to lock-up in OD (50 mph). I'll leave it sit for the short stuff now. It runs great, no smoke, vibration, etc. No idling either. I'll check mpg again after I get some highway miles into the mix.

 

[SpeedBeef]

I took several short 20-30 mile trips along with my around-town stop-and-go driving this tank, and got just over 16mpg calculated by hand. That is about the same as my 1/2 ton 5. 3 Chevy 4x4, and easier to live with than 11mpg.

 

[SWithrow]

Fueled up and hand calculated 18. 5 mixed highway and city... on 315's, imagine what I could have gotten with 265's

 

[Prairie Dog]

Fueled up and hand calculated 18. 5 mixed highway and city... on 315's, imagine what I could have gotten with 265's

Thats about what I get in mixed driving ~ somewhere between 17 and 19 usually.

 

[sluper]

Be sure to use a good fuel additive. My 2004 lost an injector @ 35-K. After that I used an additve and no problems.