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Engine, Exhaust, Diesel, Hatchback, Truck, Sedan, Wagon
This topic is for diesel car and truck owners who have not been able to find satisfactory information in the forums dealing with their particular vehicles (please use SEARCH on left of page before you post here).
#130 of 166 Re: Gas mileage [cayadopi]
by MrShift@Edmunds HOST
Jul 05, 2008 (10:46 am)
Well it's no accident that places like Texas are good for wind generators. Headwinds can really knock down mileage on a towing rig.
I kind of agree with the other posters---in the final analysis, fuel mileage on this or that diesel truck is kind of "genetic"--it's going to get what it was built to get and driving habits are probably the best way to get any improvements.
Jul 11, 2008 (9:39 am)
Thank you everyone for your input. I drive on fairly level roads. I hand calculated my mileage to and from work the past two weeks, not towing and empty, and with the outlook computer set to stock I get 18.4 MPG and with it set to towing I get 18.39 MPG. Not much difference. Now this is in heavy traffic with a lot of stop and go, some times at speeds of 62 MPH. I wanted to check this quick before I tow my trailer out to Colorado for a week leaving July 26. I was hoping to see an increase in the MPG in the tow mode compared to the stock. I Believe I have the 3.73 gears. I was wondering if the others had the 4:10 gears that were getting the better mileage. I used to have an F150 with the 3.02 gears and it didn't have the power to tow a small popup camper. I changed them to the 3.73 gears and my MPG jumped from 12 to 18 and I had no problems towing anything. I was told that the 3.02 gears kept the engine at a bad power range. I wonder if the same is true here with the 3.73 vs 4.10 gears. From now on when I ask about their gas mileage I will have to ask which gears they have.
#132 of 166 Re: Gas Milage [wisdodge]
by MrShift@Edmunds HOST
Jul 12, 2008 (7:22 am)
It is my understanding that when you have engines of considerable horsepower and torque, that ONCE they get moving and develop some forward momentum, from that point on, you wouldn't see that much difference in fuel economy if you just added another few thousand pounds to an already moving truck. Does an 18 wheeler empty vs. one with a few thousand pounds in the back on a flat highway really change its MPG? I doubt it.
Sure, if it were fully loaded with 10 tons and churning up a hill---yeah, that would eat up fuel, but for a pickup truck towing a trailer, once it got moving, I'm not surprised your MPG is close with or w/o the trailer. I'm sure that in traffic and stop and go, your MPG difference would be much more noticeable.
Jul 14, 2008 (9:09 am)
Normally I would agree, that is why I don't understand why the mileage drops so much. Most of the time I tow the highway is fairly flat, a few small hills. That is why I wonder if the gear ratio is the big difference. I would assume the 4:10 gears would hurt the gas mileage not help.
Thanks for all your input.
#135 of 166 Re: Gas Mileage [wisdodge]
by MrShift@Edmunds HOST
Jul 15, 2008 (9:00 am)
Yes lower gearing would eat up more gas (but give more low end pulling power); also there might be an aerodynamic factor at play, depending on whether you are pulling a Bullet or a Cinder Block.
#136 of 166 Re: Gas Mileage [Mr_Shiftright]
Jul 15, 2008 (11:19 am)
Yes, my trailer is a big box, which doesn't help. Last year I towed my brothers 12' V nose trailer with a couple of 4 wheelers and It didn't seem to get any better mileage. I didn't hand calculate the mileage but the onboard computer still had the same reading as my big trailer. I was surprised because I couldn't even tell his trailer was back there. I thought for sure I would get 20 MPG on that trip. He has a gas truck and he gets 18 pulling it.
#137 of 166 International 300HP VT360 Torques Curves
Jul 20, 2008 (3:16 pm)
We are looking at a RV that uses the International VT360 diesel engine. I cannot find any HP versus torque curves for the 300HP engine. Anyone know where I can locate the curves for the 300HP engine?
Aug 21, 2008 (8:08 am)
I towed the trailer from Wisconsin to Colorado and back a few weeks ago. I figure I averaged about 10 MPG and I kept my speed about 68 to 70 MPH instead of 75. My brother in-law then towed it out to South Dakota using a Ford F250 diesel that he borrowed. It was a stock truck, no chip or K&N air fileter. He said he only got about 6 MPG and he said he was going about 65 MPH to try and get the best MPG that he could to try and beat my milage.
Mar 03, 2009 (10:27 am)
2001 7.3 Excursion no start. It started this morning, hooked up my trailer harness and started fine. After we did some rewireing on the trailer harness it did not start. I unplugged the trailer harness from the truck and it did not start. It cranks good but will not light. I have replaced the CPS last year due to recall. It has never done this before.
What fuse or relay should I check. It have fuel and when I turn the key on I can hear the fuel pump/relay run.
I have disconnected the battery terminals twice to try and reset the moduel. Help!!!!