MPG with a Duramax
03-15-2010, 09:31 AM
#11
After a tune on my LBZ I get almost 20 on the highway unloaded at 80mph.
Towing around 6000-7000 lbs mixed city/highway I get about 15.5.
Haven't towed on a long highway stretch yet, but I'd guess that keeping to the speed limit (average of 70 or so) I'd probably get around 17.
Towing around 6000-7000 lbs mixed city/highway I get about 15.5.
Haven't towed on a long highway stretch yet, but I'd guess that keeping to the speed limit (average of 70 or so) I'd probably get around 17.
03-15-2010, 04:52 PM
#12
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well got back today... on the way over there i was driving 70mph and i got alot of city traffic getting out of Houston, i was pissed off cause i actually left at about 11am and figured i was going to beat the traffic and i was going to be able to cruise along but it was bad!... anyhow between the 20-25mph of terrible traffic and the rest highway, i got about 10mpg pulling the travel trailer... after reading on other forums over the weekend i read that the sweet spots for these things if towing was 60mpmh and put trans on Manual and on 5th gear (dont let it go to 6th), i did that on the way back and averaged 13-mpg... so big difference but i also didnt get no traffic in town today.... this is on a bone stock LBZ with only mod being catless and on 285 tires on 18's...... i will be changing out the stock muffler soon to open up some air way and get a very mild tune on it...
03-15-2010, 04:54 PM
#13
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by the way pulling with the Dmax is night and day difference compared to the 6.0!!!! you can barely feel a load back there..... i kept it on cruise control the whole time..... like mentioned above this was cruising at 60mph and rpms where around 1700rpm...
04-04-2010, 03:20 AM
#14
No way I can use cruise control normally if I am towing the enclosed trailer. I was able to do it some in the Texas flat areas but anywhere the ground starts varying in grade it will drop into passing gear. I have found it seems to like towing around 60 or so normally. I think a six speed would be good, I have the 4L80 so the gear changes are quite noticeable.
04-13-2010, 02:59 PM
#15
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Are you guys reading the computer projected miles per gallon or by hand in between fill ups? I have a Diablo tune with 285's and can't get better than 16-17 on the highway by itself. Around town I get 12-13 unloaded. Either something is screwed on mine (likely but haven't found what it is yet) or somebody is trusting the trip computer too much. BTW, I have the afe cold air induction, turbo back 4" exhaust and diablo tuner. If I believed the trip computer, I would be getting between 25 and 28 mpg running 63-65 to and from the beach for 2 hours each way. Ain't no way that is happening!
Last edited by OMalley; 04-14-2010 at 07:46 AM.
04-13-2010, 09:28 PM
#16
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I don't have a Duramax. 2 of my friends do (2002 and a 2006)and the both are all stock and get around 13 city and 10-11 towing 8K-9K camper and 5th wheel trailers. My mpg computer in the dash if very optimistic. It reads about 1.5 mpg high.
04-16-2010, 12:25 PM
#17
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LB7's (01-04) seem to get the best mileage, I get 17mpg in town horsing around, 23mpg on the highway both empty and playing around a bit. When I towed my buddies 21' enclosed to SC from RI last year with three bikes and all our stuff, I got 14-16 depending on how much I horsed around, def can't tell its there.
04-17-2010, 07:45 PM
#18
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Is this hand calculated or going by the DIC? The DIC is not accurate.
LB7's (01-04) seem to get the best mileage, I get 17mpg in town horsing around, 23mpg on the highway both empty and playing around a bit. When I towed my buddies 21' enclosed to SC from RI last year with three bikes and all our stuff, I got 14-16 depending on how much I horsed around, def can't tell its there.
04-19-2010, 08:05 PM
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My old man has an 03 3/4 ccsb 2wd 6 speed. He has a 27 foot Rinker Fiesta V 270. It's around 7500-8500 I believe. He usually gets 23 mpg and he was down to 15 wtih the boat, but that was back roads bringing it home. On the highway he was getting 17 i think.
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