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Your best 25/50/400 mpg

AJE
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AJE Enthusiast

AJE

Posted
Posted

Gas engine....  18.2mpg, 17.7mpg, 15.2mpg for 400 mi.

 

The 18.2 and 17.7 were set at the same trip, descending from the highest point in Ohio.  Couldn't believe when I saw that number on this truck.

 

The 15.2 was not set on a highway road trip, it was putting back and forth to work on rural roads.    Not surprisingly, the 80mph interstate driving trips don't give as good of mileage as my 50-55mph commute.

 

 

i82much Enthusiast

i82much

Posted
Posted

I would guess 17, 16, and 15, with 17 being on a country road that goes gently downhill averaging 50 mph, 16 being on a country road that is generally flat averaging 50 mph, and 15 being mostly on the interstate going 70 eastbound with a smidge of a tailwind.

91 Shortbed Chevy Enthusiast

91 Shortbed Chevy

Posted
Posted

My best has been 17.2 on a 2-hour trip to Lafayette running 60-65mph. Around town i usually get around 12. My truck has the 6.0 gas, not the diesel obviously!

johnnymordoc Enthusiast

johnnymordoc

Posted
Posted

Folks - I was seeing my mileage at 18 - 20 mpg - up until I had to replace my battery?

Not sure if it is a coincidence - not I seem to be averaging about 13.2 and best is about 16.

I have about 70K..

2014 GMC Sierra SLT.

Any thoughts?

Clean the fuel injectors?

Add an aditive to tank to clean the fuel system?

 

Thanks in advance.

JJ

Ryno12 Enthusiast

Ryno12

Posted
Posted
L5P
 
28.7 - 25 miles
26.0 - 50 miles
22.8 - 400 miles 
 
4FECD751-C184-4B77-AFA9-F9C65671D365.thumb.jpeg.33a16d95ce40edf32603489c81f4de27.jpeg

25-28.4
50-27.8
400-20.8

These can’t be HD numbers?!
SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted
11 hours ago, Ryno12 said:

 

 


These can’t be HD numbers?!

 

Sorry.  No.  I didn't catch the HD part in the title.  Sorry

Ryno12 Enthusiast

Ryno12

Posted
Posted
Sorry.  No.  I didn't catch the HD part in the title.  Sorry

Gotcha, no problem. I was thinking, damn, that’s impressive for an HD.
ewbldavis Enthusiast

ewbldavis

Posted
Posted

14, 14, and probably 14 ?

 

My "best" was at 17 when I bought truck...it's since changed to like 14.

 

Maybe it's issue with truck, or my driving style, or whatever - but she's a thirsty bitch. I love her anyway. :)

  • Like 1
i82much Enthusiast

i82much

Posted
Posted
8 hours ago, ewbldavis said:

14, 14, and probably 14 ?

 

My "best" was at 17 when I bought truck...it's since changed to like 14.

 

Maybe it's issue with truck, or my driving style, or whatever - but she's a thirsty bitch. I love her anyway. :)

sumbitch can handle anything though!

zmnypit Enthusiast

zmnypit

Posted
Posted (edited)

15 HD Deleted/tuned Duramax on 33x12.50x20. No interstate all around town 35-60mph. 

 

25-21.2
50-19.7
400-18.4

Edited by zmnypit
redwngr Senior Enthusiast

redwngr

Posted
Posted
On 12/17/2019 at 9:58 AM, SILVER SLED said:

25-28.4

50-27.8

400-20.8

 

On 12/17/2019 at 9:44 PM, Ryno12 said:

These can’t be HD numbers?!

 

Sure they can....

When a Cdn truck is set to inch units instead of metric, it displays mpg for 31/62/404 instead of 25/50/400

 

My L5P currently is at

31  - 34.1

62 - 29.8

404 - 24.4

 

It has lots and lots of full tank averages over 20 mpg which means 600 miles between fillups.  On flat 2 lane with no wind I get the 'last 31' over 25 regularly.

Yes, it does lots of steady state driving with cruise on.

No, it doesn't tow much. 

 

DEF is a little over 1100 mpg.

 

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