Thought it would be interesting to chart the fuel efficiency at various speeds, so when the tank is almost on empty, I'd know how fast to drive to go as far as possible.


Truck is an extended cab, long bed, 2 people in cab, full tank, tool box, climate control running, level highway, no wind, no engine mods, on cruise control.


MPH MILES PER GALLON


35 21


40 25


45 25


50 27


55 25


60 23


65 22


70 20


75 18 (truck's top speed http://www.dieselplace.com/forum/smileys/Cry.gif)


So.........drive at 50 for most efficient use of vehicle, and never step hard on the accelerator.


Will be taking an 11,000 lb 5th wheel out in a couple weeks and will do the same test. Am betting that 50 to 55 is still going to be the sweet spot...unfortunately at about 10 mpg probably.

Curious, why is your top speed only 75 mph? http://www.dieselplace.com/forum/smileys/Ermm.gif

Steve,


I'm surprised you would even ask such a question. 75 is the maximum legal speed limit in the USA. Only 70 for you here in california. It's just a crying shame that we need to let off the accelerator when we reach those speeds.

Oh...now I see why you would ask such a question. You are one of those "hot-rodding" types, aren't you. It seems you have a real Attitude problem.

75mph is hardly keeping up with the flow of traffic around here.And in montana I believe there are some roads with out speed limits I had a 18wheeler pass he was doing a 100mph atleast

socal...


I do like your idea of the police siren. Of course, use of such a device on public roads would be illegal. But there are so many instances that it would be fun to have.


Illegal on one hand. Fun on the other. What to do?


Got any good stories?

ya is your police sirens the us ones or eropean ones? jw and where did u get them?

I would be very pleased to get those results.


I have 5000 miles on my LLY and the best I have seen is 13.6 average over a 200 mile trip.


How many miles do you have on your LLY?


Thanks


Brent Peterson

Brent,


That is horrible mileage. Either something is wrong, or you have the pedal to the metal all the time! I do drive pretty conservatively, so my mileage will be a bit better than most. I use the "egg under the foot" method.


I've got about 7,000 miles on mine now, but average mileage (without the 5th wheel and on level ground) has always been at least 16 mpg and as high as 19, depending on speed driven.

I get 13.2 with a VERY light foot. If I drive like I want, I get 11.0....I tried my hardest to get to 15 MPG on a tank, couldn't even come close. I live too far away from an interstate, and do mostly stop-n-go traffic to work for 8 miles. Those that get 15+ MPG drive on country roads with zero stops and no city traffic. If I set the cruise on the interstate at 68 mph and watch the instant fuel economy, my DIC shows 14 MPG. I GPS'd my truck with my 265's (tires) and shows to be within a tenth of a mile over a 10 mile stretch.

Rollin' - so youre the one out there driven your dmax like a grandma going to a funeral polar http://www.dieselplace.com/forum/smileys/HiHi.gif makes us common folk look kinda slow to the other diesel owners http://www.dieselplace.com/forum/smileys/Angry.gif

tbone,


Yes, I'm the old Dmax owner that all the other Dmax owners fly by on the highway.


If I still owned my homebuilt V-8 Corvair, I'd learn all them young'uns with their fancy "engine boxes" a thing or two about fast vehicles (except maybe for McRat's Vette).

somethin smells fishy.


I edited because I was a big ole meany in the original post.Edited by: dpower

TKDURAMAX,


I'm kind of in the same boat as you so to speak. I live about 3 miles from work, all very low speed roads and NO highway. I routinely get about 11.5. Where I differ is in highway MPG. I just took a 3000 mile trip from Newport, RI to Clearwater, FL (and a few other stops) and I got 20.8 on the highway (this is by the DIC, I suspect actual is a little lower, maybe 1 MPG lower). I wonder if your bigger tires are making that much difference, plus you are a 3500, I'm 2500HD. Interesting to ponder at least.


Dennis

This rollin thunder guy is a retard ...read his other thread in here about his "Muffler Problem".....somethin smells fishy.

You're not gonna last long on this forum if you run around calling people retards. I think you need to re-read the Mufler Problem thread and you will realise that it is nothing more then a joke.

This rollin thunder guy is a retard ...read his other thread in here about his "Muffler Problem".....somethin smells fishy.


dpower - i suppose u run around telling kids there is no Easter bunny either...oh crap, I let the cat out of the bag!http://www.dieselplace.com/forum/smileys/HiHi.gif

TKDURAMAX,


I'm kind of in the same boat as you so to speak. I live about 3 miles from work, all very low speed roads and NO highway. I routinely get about 11.5. Where I differ is in highway MPG. I just took a 3000 mile trip from Newport, RI to Clearwater, FL (and a few other stops) and I got 20.8 on the highway (this is by the DIC, I suspect actual is a little lower, maybe 1 MPG lower). I wonder if your bigger tires are making that much difference, plus you are a 3500, I'm 2500HD. Interesting to ponder at least.


Dennis








Dennis,


How many miles total on your truck so far? I have 3100 or so. I wonder about areodynamics also......Maybe going to synthetic oil may help after break in.http://www.dieselplace.com/forum/smileys/Ermm.gif

I tell kids there is no santa claus by the way. You have to admit if ya read some of this thread then his other you have to be suspicious. Max Power...if I ruffled your feathers sorry. Lots of stuff runnin around this forum lately that has been gettin under my skin as well as others. I have to learn just to let things go. Honestly that muffler thread is just not funny...maybe the first fifty times we heard the old muffler bearing thing it was funny. By the way...being the "politician" I am I will edit the above post...ya know its an election year and image is everything! Edited by: dpower

Sorry guys...I had no idea owning the Duramax was such a serious matter. I'll try to refrain from diesel related humor in the future.

http://www.dieselplace.com/forum/smileys/HiHi.gif http://www.dieselplace.com/forum/smileys/Rock On.gif

http://www.dieselplace.com/forum/smileys/Confused.gifNever said it was serious Mr. Thunder...some things are funny to some and not to others.

Well, if I didn't have the camper on the back, I'd fill in the table:
80 = ?
85 = ?
90 = ?
95 = ?
100 = ?
110 = ?
115 = ?

Someone go out and try it!

KTDURAMAX (Got it right this time),


I've got about 11000 on mine. As far as aerodynamics, I'd say yours looks pretty slick to me.http://www.dieselplace.com/forum/smileys/Big Smile.gif Seriously, probably a negligible difference there. Let us know how the synthetic works. If there is a big difference I will consider it (but the difference would probably be realized more in engine longevity rather than MPG, what do you think?)


Dennis

tswartos,


What do you mean, "there's no easter bunny"?


Dennis

Oh crap,


Some one shot and skinned the Easter bunny http://www.dieselplace.com/forum/smileys/Question.gif http://www.dieselplace.com/forum/smileys/Cry.gif


Bunny, it's the other white meat http://www.dieselplace.com/forum/smileys/Clap.gif

tswartos,


What do you mean, "there's no easter bunny"?


Dennis





Oh crap, I mean no Santa Claus.....doh did it again..argghhhttp://www.dieselplace.com/forum/smileys/Cry.gif

This is what happened to the Easter Bunny.......http://www.dieselplace.com/forum/smileys/Cry.gif


http://www.dieselplace.com/forum/uploads/Easter_bunny_dead.jpg

LOL,


Are those duramax tracks I see down the middle of that hare?


Dennis

lmao..now thats funny!

Got 6K miles now and the best mileage 14.5 mpg on the highway with cruise on at 73mph. No way to drive 55 without getting a semi up the tailpipe. http://www.dieselplace.com/forum/smileys/Geek.gif I get about 12-13 city.


So how can you test a truck at over 100mph? I guestimate that I'd hit redline at about 98mph.http://www.dieselplace.com/forum/smileys/Stern Smile.gif

not sure about the redline @ 98 - ive had mine up to 115 and it was still pulling hard and i wasnt toooo high on the rpm that i had to worry about it http://www.dieselplace.com/forum/smileys/HiHi.gif

The redline is right at 98mph...you can get 125mph with your tts tow tune....part of the programing.

KTDURAMAX - lmao....i think i pizzed my pantshttp://www.dieselplace.com/forum/smileys/HiHi.gif