Engine/Transmission (1998.5 - 2002) V10 vs I-6 MPG Wishful Thinking

[diesel DOG]

Going from Long Island to Pocono with my Corvette on a 22' open trailer, tools, 2 sets of tires I get 14. 9 @ 65. Set the cruise on a nice level sea side road I get 23 @ 50 MPH with 1500 lb. of tools in the back. Towing 12,000 lb. I got 12 MPG. I am happy. They must call her lightfoot if she gets 16. I have never heard of that in my life and I did ask around.

 

[Pit Bull]

Only have 11,000 miles on my 2002 3500RC 4x4 ETH/DEE with 3. 55's but I don't think I am close to having it broken in. I never tow or haul much and the mileage is improving. I am now getting 18 mpg around town. But last week I drove on the highway for most of 200 miles doing in the 70+ mph range and only got 16 mpg. I thought I was going to get 20+ My truck weighs 7000 lbs with me in it, and I know that even the wind can make a difference. But I expect this truck to get 20 mpg combined summer and 18 mpg combined winter after it get 20K miles on the it. Think I am realistic?

 

[outlawram]

I had a 98 v10 and it would pass everything but a gas station. I got 10-11 when not pulling and 4-5 when pulling. It sucked! I will never own another one. And they sound like crap too.

 

[R-N-R]

It is hard for me to cry about 10mpg towing when I was getting 4. 5mpg towing and 11mpg around town with my '99 5. 9 V8.

 

[Big Dawg]

Originally posted by jponder

What about your throttle control? Cruise or foot when you posted your big numbers

JPonder... .



I use a combination of the two but usaully use the cruise on the highway once I am up to speed which for those big numbers was about 50 to 55 miles an hour. Also for city driving I do a lot of in gear coasting and will time the traffic lights so I can minimize coming to a complete stop. It takes a lot of fuel to get these trucks moving.

 

[Scrappy]

mileage

My truck has 25k. miles, I don't know if it is broke in yet 'cus I really haven't towed yet. My best in my current configuration is 17. 25 mpg. during the summer doing mostly interstate driving. My worst is during the winter just driving to and from work (7-8mi. at a time) This weekend I am towing a 27' TT for my neighbor so I can break the truck in. I'll see what I get while towing.

 

[DKupfrian]

I was wondering the same thing. When I bought my truck new in 2000, I kept all fuel receipts and calculated by hand my milage. Let me tell you that at 60,000 miles my milage is still increasing. These trucks are not fully broken in until you hand the keys over to your grandson!



BTW

first year averaged 16. 5

second year averaged 17. 5

third year averaged 18. 5

forth year looking like it will be 19-20

4x4 with automatic



enjoy

 

[jponder]

Originally posted by Big Dawg

JPonder... .



I use a combination of the two but usaully use the cruise on the highway once I am up to speed which for those big numbers was about 50 to 55 miles an hour. Also for city driving I do a lot of in gear coasting and will time the traffic lights so I can minimize coming to a complete stop. It takes a lot of fuel to get these trucks moving.

I do that also. Everytime you hit the brake you have messed up. If you could drive and never hit your brake it means you are doing good. What do you mean by in gear coasting. I coast totally out of gear. Its a great way to let the turbo cool down. Just come off throttle when you see your exit and coast on off. These trucks will coast real good because they are so heavy.

 

[Big Dawg]

Coasting out of gear uses fuel... Coasting in gear (manual transmission) uses no fuel.

 

[jponder]

Originally posted by Big Dawg

Coasting out of gear uses fuel... Coasting in gear (manual transmission) uses no fuel.

Coasting out of gear uses the fuel of idling. when you kill all fuel you arent coasting you are engine braking. If I am going down a hill and take my foot off the pedal I am not coasting I am engine braking . Elaborate some more on what you are saying

 

[Big Dawg]

JP...



I'm trying to get out of here to go to the airport... I'll respond back in detail later. Everyone have a happy Fourth of July!!!!

 

[RustyJC]

Towing a 13,500 lb 13'2" tall (top of front A/C) 5th wheel at 65-70 MPH in mixed flat & hilly terrain (Houston into the Texas Hill Country to Fredericksburg), we get around 10. 5 MPG with the Cummins. This includes a stretch through Austin city traffic. Our previous V-10 got 6. 5 MPG pulling the same 5ver over the same route.



We just got back from a round trip from Houston to Nashville, TN. Running 70-72 MPH on I-40 in Tennessee, I would get around 10. 5 MPG. Running 65 on I-40 and I-30 in Arkansas (lower speed limit for trucks), mileage increased to 12 MPG.



I've never run either truck through a full tank of fuel when not towing, so I have no idea what mileage they would get under unloaded conditions.



Rusty

 

[jponder]

Originally posted by Big Dawg

JP...



I'm trying to get out of here to go to the airport... I'll respond back in detail later. Everyone have a happy Fourth of July!!!!

RIGHT NOW BUDDY! Where are your priorities! what is more important than the search for the 30 MPG holy grail of Dodge Cummins!

 

[WadePatton]

Yeah, more on this coast business

I can coast by pushing in the clutch or by shifting out of gear. Not much difference there.

Or I can lift while in gear and decelerate by the braking effect of the engine. This shortens the "coast" considerably.



And note that my EGT's drop way more in gear than out of gear. I figure because I'm getting more air (via RPM) and the same amount of fuel.



When your Cummins goes to zero fuel consumption--it gets really really quiet.

 

[jponder]

Re: Yeah, more on this coast business

Originally posted by WadePatton

I can coast by pushing in the clutch or by shifting out of gear. Not much difference there.

Or I can lift while in gear and decelerate by the braking effect of the engine. This shortens the "coast" considerably.



And note that my EGT's drop way more in gear than out of gear. I figure because I'm getting more air (via RPM) and the same amount of fuel.



When your Cummins goes to zero fuel consumption--it gets really really quiet.

Look at the other post about this. Do you think in gear coasting delivers better mileage?

 

[WadePatton]

Acceleration is where the MPG goes--for me anyway. Wind resistance at 50+ mph is the other big consumer of fuel.



I'm not going to change my cruising speed requirements, but if I could accelerate a bit easier, I'd see much improved economy.



Coasting, "in gear", out of gear, pants down--I don't think amounts to a hill of beans.



YMMV!

 

[jponder]

Depends on what kind of Beans your talking about

 

[GMocanu]

I just put Amsoil in the rear and it coasts (out of gear) a lot better now. Big difference.

 

[Big Dawg]

Again...



Coasting in gear with a manual transmission on these trucks should use zero, zip, none, nada fuel. Coasting out of gear with a manual transmission will use some fuel to keep the engine running although not much. I use this method all the time especially when coming up on a stoplight that is red or getting ready to turn red.

 

[WadePatton]

I think some of us are of the opinion that if it's in gear, you're NOT coasting.



As far as it shutting the fuel off completely, I am upset about this. What about my VP? Is it getting enough flow through for cooling?



I have seen the EGT's go under 200 on a long IN GEAR DECELERATION.



Coasting it won't go under 250--but I get to the bottom of the hill faster. Oo.