How to squeeze more MPG's from my 2005 Cummins?
11-02-2009, 11:31 AM
#16
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i picked up about 2 mpg using my smarty jr on economy with max timing.
the g-56 is geared low, so it gets worse mileage than the autos. the mpg numbers cited above by the OP, is that hand calc, or overhead? the overhead is usually a little optimistic. i get 19 hand calc, gps speedo adjusted now with the JR and 285/70r17 tires.
the g-56 is geared low, so it gets worse mileage than the autos. the mpg numbers cited above by the OP, is that hand calc, or overhead? the overhead is usually a little optimistic. i get 19 hand calc, gps speedo adjusted now with the JR and 285/70r17 tires.
11-30-2009, 05:26 PM
#17
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11-30-2009, 11:04 PM
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I just gor back from a trip to Roy, UT. Near Ogden.
The smarty jr. is set on economy, PoD 65.
On the back roads I got 22mpg. On I-80 cruising at 78, I got 18mpg. That's hand calculated. Not bad, I think. My 5.9 gas Dakota generally averaged about 11mpg on that trip.
The problem with making mods for mileage is the cost of the mods. As above, you have to calculate how long it will take to break even. It's often quite a while. Something like a gear vendors overdrive could take 5 years to break even on. A lot of people don't own their vehicles that long.
If you mostly drive empty or with a light load, you could install a taller tire. That's a common expense anyway, so we're not talking about complexity or big bux.
The smarty jr. is set on economy, PoD 65.
On the back roads I got 22mpg. On I-80 cruising at 78, I got 18mpg. That's hand calculated. Not bad, I think. My 5.9 gas Dakota generally averaged about 11mpg on that trip.
The problem with making mods for mileage is the cost of the mods. As above, you have to calculate how long it will take to break even. It's often quite a while. Something like a gear vendors overdrive could take 5 years to break even on. A lot of people don't own their vehicles that long.
If you mostly drive empty or with a light load, you could install a taller tire. That's a common expense anyway, so we're not talking about complexity or big bux.
12-01-2009, 09:50 AM
#19
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I just gor back from a trip to Roy, UT. Near Ogden.
The smarty jr. is set on economy, PoD 65.
On the back roads I got 22mpg. On I-80 cruising at 78, I got 18mpg. That's hand calculated. Not bad, I think. My 5.9 gas Dakota generally averaged about 11mpg on that trip.
The problem with making mods for mileage is the cost of the mods. As above, you have to calculate how long it will take to break even. It's often quite a while. Something like a gear vendors overdrive could take 5 years to break even on. A lot of people don't own their vehicles that long.
If you mostly drive empty or with a light load, you could install a taller tire. That's a common expense anyway, so we're not talking about complexity or big bux.
The smarty jr. is set on economy, PoD 65.
On the back roads I got 22mpg. On I-80 cruising at 78, I got 18mpg. That's hand calculated. Not bad, I think. My 5.9 gas Dakota generally averaged about 11mpg on that trip.
The problem with making mods for mileage is the cost of the mods. As above, you have to calculate how long it will take to break even. It's often quite a while. Something like a gear vendors overdrive could take 5 years to break even on. A lot of people don't own their vehicles that long.
If you mostly drive empty or with a light load, you could install a taller tire. That's a common expense anyway, so we're not talking about complexity or big bux.
I'm just curious as to opinions of other dodge enthusiasts here on DTR.com
-G
12-01-2009, 10:06 AM
#21
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MPG Max
I posted this awhile back to a mileage question:
"I had a long trip from mid-Maryland to Providence, RI and back, about 850mi. I went north into PA on a road I hadn't traveled before so I stayed mostly at the 55 mph speed limit. It was a cool day and I was solo on the first leg. Got 23.7 at fill-up in RI. Coming back I had to go through NY/NJ on 95 including a long back-up on GW Bridge. Filling at the same station where I started, I got 21.3 for the return trip. All hand calculated; overhead liar said 26.1 for the whole trip.
Not bad for a 8K lb brick."
I have pretty much the same truck as you do (see sig). One thing I didn't mention is that I am on my second set of stock Michelins, which I keep aired up to 60 psi.
"I had a long trip from mid-Maryland to Providence, RI and back, about 850mi. I went north into PA on a road I hadn't traveled before so I stayed mostly at the 55 mph speed limit. It was a cool day and I was solo on the first leg. Got 23.7 at fill-up in RI. Coming back I had to go through NY/NJ on 95 including a long back-up on GW Bridge. Filling at the same station where I started, I got 21.3 for the return trip. All hand calculated; overhead liar said 26.1 for the whole trip.
Not bad for a 8K lb brick."
I have pretty much the same truck as you do (see sig). One thing I didn't mention is that I am on my second set of stock Michelins, which I keep aired up to 60 psi.
12-01-2009, 10:16 AM
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12-01-2009, 10:19 AM
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i picked up about 2 mpg using my smarty jr on economy with max timing.
the g-56 is geared low, so it gets worse mileage than the autos. the mpg numbers cited above by the OP, is that hand calc, or overhead? the overhead is usually a little optimistic. i get 19 hand calc, gps speedo adjusted now with the JR and 285/70r17 tires.
the g-56 is geared low, so it gets worse mileage than the autos. the mpg numbers cited above by the OP, is that hand calc, or overhead? the overhead is usually a little optimistic. i get 19 hand calc, gps speedo adjusted now with the JR and 285/70r17 tires.
-G
12-01-2009, 01:45 PM
#25
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you have to get rid of the in cylinder egr that is used on your truck. do the following three things and your oil will stay cleaner, egt will drop 350* and mpg will increase 40%. change the cam to a pdr, and change the nozzles to 50hp at the same time to save on labor. next is the smarty jr. the cam restores exhaust valve timing. the 50hp nozzles does three important things with duration and effective timing. and the smarty to restore timing. leave the smarty on economy or tow. the efficiency gain adds so much torque on the low end that your clutch can not take the third setting
12-01-2009, 05:50 PM
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just recently i g0t 26.2MPG (without the smarty) on the highway with a trip from Seattle to LA (CA). I get a constant 19-21MPG with daily driving mixed highway and city. But this is the perks of a 2wd with highway tires.
12-02-2009, 04:20 AM
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After you've changed your driving style to economy mode then try the following.
Max air pressure, change all your fluids to synthetic. Tall skinny tires when you need new biscuits.
Everything else is going to take some time to pay back.
Max air pressure, change all your fluids to synthetic. Tall skinny tires when you need new biscuits.
Everything else is going to take some time to pay back.
12-02-2009, 08:34 AM
#29
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I agree and have looked into these "solutions" also concerning the cost to benefit ratio. I'm currenlty in the Navy and one of the sailors on my ship told me how his dad put in the double rear end and that he was getting around 30 mpg. Are all these stories people say about that stuff just crap? I always wonder when reading these forums sometimes. He was telling me his dad went from doin 70 at 2250 rpms to 70 at 1600 rpms and that is a freaking huge difference in the amount of gas used. The only point that would concern me is loading up the engine at low rpms like that w/ fighting wind resistence, hills, road friction, etc.
I'm just curious as to opinions of other dodge enthusiasts here on DTR.com
-G
I'm just curious as to opinions of other dodge enthusiasts here on DTR.com
-G
12-02-2009, 09:38 AM
#30
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I agree and have looked into these "solutions" also concerning the cost to benefit ratio. I'm currenlty in the Navy and one of the sailors on my ship told me how his dad put in the double rear end and that he was getting around 30 mpg. Are all these stories people say about that stuff just crap? I always wonder when reading these forums sometimes. He was telling me his dad went from doin 70 at 2250 rpms to 70 at 1600 rpms and that is a freaking huge difference in the amount of gas used. The only point that would concern me is loading up the engine at low rpms like that w/ fighting wind resistence, hills, road friction, etc.
I'm just curious as to opinions of other dodge enthusiasts here on DTR.com
-G
I'm just curious as to opinions of other dodge enthusiasts here on DTR.com
-G
1. getting the 3.43 gears and running 40" tires.
2. They have the new 6sp auto tranny with larger tires
But even with that, it wont help in fuel economy. Just because you lower your RPM doesnt mean better fuel mileage, there is a good chance they are lugging the engine. The ecm will put more fuel in without adding the extra boost needed.