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Poor mpg

2360 Views 16 Replies 12 Participants Last post by  fryboy22
We have a 02 Cab and Chassis 4x4 flatbed witht the h.o. engine and a 6sp. manual transmission and 3:55 gears. Uncle is complaining that he is only getting 15 mpg out of it even on extended trips on the highway. It is 100% stock.

What can we do to improve mpg? We have a new air filter. We also have a superchips programmer on the way. Should we open up the exhaust or any other ideas?
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i would love to get 15mpgs. i am only getting 10-11mpg's. Some of it is the winter grade diesel fuel. more open exhaust and air filter will help also
 

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i have an 01 HO 6spd dually, and cant get above 16 bought it in oct, so ive only seen winter blend. thought i had my programmer set up wrong, still nothin, st8 pip, and BHAF, atill about 15.8 hand calculated i also run diesel supplement (white bottle) and howes anti gel. i would love to get better mpg's. but my 04 only gets 10mpg, so it beats that at least! :hehe:
 

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Bigger exhaust.
BHAF air filter.
TWC3 2cycle oil in fuel at 1oz per gal.
Keep highway speed at 60mph or less.
Easy accelleration no full throttle starts.
If you have a pyro gauge try to keep your exh temp below 650.
Keep it in the highest gear without lugging the engine. (Drive like an old lady)
Don't let sit and idle when you don't have to.
You will get better milage when it gets warmer out and the fuel is a summer blend.
Your driving habits have more to do with milage than truck modifications do in most cases.
 

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Bigger exhaust.
BHAF air filter.
TWC3 2cycle oil in fuel at 1oz per gal.
Keep highway speed at 60mph or less.
Easy accelleration no full throttle starts.
If you have a pyro gauge try to keep your exh temp below 650.
Keep it in the highest gear without lugging the engine. (Drive like an old lady)
Don't let sit and idle when you don't have to.
You will get better milage when it gets warmer out and the fuel is a summer blend.
Your driving habits have more to do with milage than truck modifications do in most cases.

I like it Jimbowe !!!!! :thumbsup:
 

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best I ever got was around 19 with a strong tail wind across SD, average,,,,, 14-15, I weigh 9,000LBS and drive aggresively..... the 19 came at 60-65mph, 1800RPM 2cycle, Stanadyne fuel treatment, cool temps, 4" to 5" open exhaust, opened up stock air box, on a stock engine. while running empty, my gear ratio and weight hinders me from getting up in speed. On long hauls I have a locking throttle cable under the dash that will lock the throttle at the least amount of fuel to keep that speed on a flat straight away,,, have to help it with the foot on the bumps.... this is how I got the 19, but havent seen it since in my daily runnings.
 

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Bigger exhaust.
BHAF air filter.
TWC3 2cycle oil in fuel at 1oz per gal.
Keep highway speed at 60mph or less.
Easy accelleration no full throttle starts.
If you have a pyro gauge try to keep your exh temp below 650.
Keep it in the highest gear without lugging the engine. (Drive like an old lady)
Don't let sit and idle when you don't have to.
You will get better milage when it gets warmer out and the fuel is a summer blend.
Your driving habits have more to do with milage than truck modifications do in most cases.

^^This is will help for sure!


A good injector cleaner additive will help also. An edge ez can give you a mile or two. I get 17-18 (hand calculated) with a mix of intown and highway. Straight highway i can squeeze a little more.
 

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We have a 02 Cab and Chassis 4x4 flatbed witht the h.o. engine and a 6sp. manual transmission and 3:55 gears. Uncle is complaining that he is only getting 15 mpg out of it even on extended trips on the highway. It is 100% stock.

What can we do to improve mpg? We have a new air filter. We also have a superchips programmer on the way. Should we open up the exhaust or any other ideas?
My truck is an 00 3500 4x4 QC with the 6-spd (NV5600) and 3.55 gears. I can still get fairly good numbers imo (17-18mpg) in the winter going down the highway. However I get these numbers with nothing in the bed, going 55mph in overdrive, and watching how fast I brake/accelerate.

Acceleration and overall road speed are going to be the biggest killers of mileage in a truck this size with the aerodynamics of a brick.

It's pretty much an understand rule that for every 1mph over 55mph you can expect a 1% drop in fuel economy. However this is a rough figure you will actually start losing mileage even quicker past 65mph.

So convince him to enjoy the scenery and drive slower and see what he gets then. If it is still low after that you can probably blame winter fuel. However I would check the obvious. Tires, alignment, brakes, etc...
 

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reset, APPS (TPS) Turn key to ignition,(do not start) Depress pedal slowly fully, 3 times,,, turn ignition off, then start your truck,,,,, there are other methods via a volt meter, this is the quick method told to me by a Cummins Tech, if this doesnt help with dead pedel, then there is a code that has to be cleared.
 

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how do you do this?
What you people are calling a TPS is really an APPS Accelerator Pedal Position Sensor (APPS).

Read here on how to reset:
APPS Sensor

Everyone should bookmark Mopar1976Man's site. It has a welth of information on our trucks.
2nd Gen 24V :thumbsup:
 

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reset, APPS (TPS) Turn key to ignition,(do not start) Depress pedal slowly fully, 3 times,,, turn ignition off, then start your truck,,,,, there are other methods via a volt meter, this is the quick method told to me by a Cummins Tech, if this doesnt help with dead pedel, then there is a code that has to be cleared.
Sorry, that procedure won't work unless the batteries have been disconnected for at least 30 min then re connected.
See the APPS link in my previous post.:S:
 

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Bigger exhaust.
BHAF air filter.
TWC3 2cycle oil in fuel at 1oz per gal.
Keep highway speed at 60mph or less.
Easy accelleration no full throttle starts.
If you have a pyro gauge try to keep your exh temp below 650.
Keep it in the highest gear without lugging the engine. (Drive like an old lady)
Don't let sit and idle when you don't have to.
You will get better milage when it gets warmer out and the fuel is a summer blend.
Your driving habits have more to do with milage than truck modifications do in most cases.
I just made a trip up to NJ up 95 and averaged 20 and thats at 75 mph with my adrenaline set at 3
 

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I just made a trip up to NJ up 95 and averaged 20 and thats at 75 mph with my adrenaline set at 3
Had you driven at 60 you most likely would have seen 25 mpg. I've seen 25 on my truck highway driving with no load and ideal conditions (flat roads no wind).:thumbsup:
 

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I'm glad im not the only one that gets good Mpg. I was beginning to think I was crazy. I usually get 20-21 mpg not really thinking about my driving to much. I've calculated 24 in the summer time and on one trip i'm sure I got even better ! It takes patience to get that kind of milage though !

winter time is a different story ---- not getting much better than 18 right now.
 

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:agree2:I was worried when I first read this... thought I forgot how to do math or something. This weekend I calculated 23.9 one way and 21.3 coming back (I can still adverage 18 with all in town driving and 15-17 towing- depends on weight)- mind you this is a 4x4 rig too. I keep it under 65mph and 2,000 RPMS. I drive it like a grandma, use KLEEN additive or Howes, there is no exhaust just pipe, Big KN Air, and I run Lucas treatment in the oil and gear boxes. I also run the chip on either mileage setting or going up long grades I bump it to the 90hp setting to keep the rig from lugging and try to keep the boost number low when I can. I also coast when the oppertunity arises. I'd say 80% is how you drive and the conditions and the other 20% is how well the rig is running and tunned
 
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