Posted by Mr.PG on Wednesday, July 29, 2009 at 16:57:30 :
In Reply to: Re: Diesel mileage posted by Marty on Wednesday, July 29, 2009 at 16:27:51 :
this is only my thoughts from my experience of having lived in Colorado and driving a diesel in them,
When I used to come out here on trips from Wi, to CO, I would get about 11.5-12 mpg towing a 40 foot gooseneck trailer out on the plains or prairie states. That was manually checking my milage.
(I have never owned a truck with one of those computer controlled read outs I have been told that they are worthless so I never payed for that option. Kind of neat to look at, but never wanted to pay for one)
When I got into the rockies my milage always went up, I would get about 13.5-14 mpg towing the trailer in the mountains.
I always thought it od that it went up, even though I was in higher altitudes with less air, like Marty stated, but I have alwasy got about the best mileage in the mountains.
This is what I think happens, so you drive for 10-12 miles up some long grade using the gas pedal most if not all the time, but when you get to the top, you stop using the pedal and just coast on down the other side 10-12 miles never toching the pedal, so your fuel milage is going to come up right?
My dad has newer car that has one of those computer controlled overhead mpg things. Having driven it my way that I am looking at this makes sense. I have driven his car, if you take off from a dead stop and floor it and keep the pedal to the metal, you can get the mpg readout to get donw to 4-5 mpg, but when you let off it comes way up!! If you go down a big hill and cost the whole way donw you can get it to read into to the high 50's mpg or low 60's mpg.
These are only my thoughts from having driven in the mountains. Yes you use the fuel up hill, but not down hill, or thats is just the way I drive, when going down hill I alwasy have enough weight behind me that I don't need to use the fuel, brakes if anything is all I use. Just let gravity do the work, not the 5.9, it got you to the top!!
When I moved east last year the moving van we rented to move the household stuff, had a computer controlled read out on the dash, same thing. Going up the passes it got down into the single digits, but coasting down the hills in would climb into the 50's mpg.