Jump to content

I'm getting raped on mileage

shuug

Recommended Posts

shuug Enthusiast

shuug

Posted
Posted

My duramax is getting 11.5 mpg. I have 287 75 16's on it and I'm thinking maybe the computer is sensative and I need to get it recalibrated?

 

Also, I'm ordering the edge juice 125hp and was wondering if I also have to get a new exhaust? If I need I new exhaust what kind should I get? I want it to whistle...

 

thanks

Shaners Senior Enthusiast

Shaners

Posted
Posted

When you figure out your milage do you consider the fact that your speedo/odo may be off as much as 6% over the stock 245/75's? The larger tires are heavier and will have more rolling resistance, but your MPG's should be better than what you're getting.

 

A recalibration should move you shift points back to optimum, and that may help your MPG's.

Frank S Senior Enthusiast

Frank S

Posted
Posted
My duramax is getting 11.5 mpg. I have 287 75 16's on it and I'm thinking maybe the computer is sensative and I need to get it recalibrated?

 

Also, I'm ordering the edge juice 125hp and was wondering if I also have to get a new exhaust? If I need I new exhaust what kind should I get? I want it to whistle...

 

thanks

Definitely go with a new down pipe-back exhaust to keep your EGT's from getting too high.

 

Don't know on the problem but I'd get it checked before juicing the truck.

rascal Enthusiast

rascal

Posted
Posted
My Silverado with the 6.0 gets mainly 8city and 15highway, Bravada with 4.2 is at 13.9city.........now you know why we got a Vibe for runnin around!

what kinda mods have you did?

01silverado2500 Enthusiast

01silverado2500

Posted
Posted

Both are stock, they just make short trips and the roads are hilly here in western PA. The truck is stock 4x4 with the 6.0 and 4.10 gears. Bravada is stock with AWD and 3.73 gears. Ive had a few other big chevys with 350s in them and got close to the same mpg. Both the truck and Bravy are big and heavy so I just have to feed them.

Machine Enthusiast

Machine

Posted
Posted

An adjusted 11.5-mpg is not really normal for a DMax... Best to have that one checked out before adding any type of power mod. It’s probably not an injector issue. If it was, you would have many more problems than just some $hitty mpg’s

 

Regarding the Edge Juice…. Even more important than the 4” aftermarket exhaust are GUAGES. But it sounds like you’re getting the Juice with the Attitude controller, yes? If not, check into the gauges before adding a power mod.

 

Some good 4” exhausts are Banks, DPPI, Quadzilla, and Bully Dog. I have the DPPI 4” w/ the 5” tip and it’s a very good system. Don’t expect to hear too much turbo “whistle” with any of these, though. The DMax turbo doesn’t sing as loud as the new 6.0 Ford PS’s with 4” pipes. The ’03 Fords sound like an F-16 coming down the road. The 04’s and 05’s are a little more subdued

Machine Enthusiast

Machine

Posted
Posted
Those mpgs are not normal. Like someone said, your speedometer could be off.

 

Machine, are you going to do anything to your new PSD?

Hi –

 

Yes, next week it’s going to Dallas to have a 4.5” suspension lift installed. It’ll sit on 315’s. As far as the engine - I know Quad at Quadzilla, so I’ll probably run one of his programmers until I figure out what the best combination for power and reliability is. I run his programmer on my Duramax and it’s been a good performer.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.4k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    342,860
    Total Members
    8,960
    Most Online
    HWN808
    Newest Member
    HWN808
    Joined

  • Who's Online   4 Members, 0 Anonymous, 1,004 Guests (See full list)

  • Latest Articles

  • Posts

    • OnTheReel
      Some Assembly is Required

      By OnTheReel · Posted

      https://www.gm-trucks.com/why-gm-chose-0w-30-gen-6-v8-oil/   The swing back to reality continues…
    • richard wysong
      Gas Prices

      By richard wysong · Posted

      Diesel $5.42 at the truck stop on the hi-way
    • Chuck FB
      Joke Thread

      By Chuck FB · Posted

    • txab
      Gas Prices

      By txab · Posted

      $3.59  
    • needafix
      2019+ Brake failure, it's complicated

      By needafix · Posted

      I'm not sure if this should be a new topic, let me know if it's out of place. This my first post. Thanks 85077522 - AC Delco GM Genuine Parts Brake Master Cylinders. Anyone else had to replace this brake master cylinder yet. I didn't do any brake work, it looks like new parts and I've had the truck for about 4k miles, 119k total miles.  When it started to throw codes I did the calibrations with a bidirectional scanner and got the codes to clear but they came back so I did the routine; base bleed, automated bleed and final base bleed. All that with Bosch ES16-32N fluid (please look it up). That seemed to fix it but 100ish miles later it failed again so I ran the same process but with a pressure bleeder this time and got the same results, fixed for 100ish miles. The original fluid looked bad and I thought I got most of it out, it could've been the wrong fluid. The codes; P25A2, C05B0-00, C2A1B. I can get them to clear but not for long. The C05B0 indicates a leak in the front circuit (which is bone dry) so I'm thinking of doing the bleed process on that front again today and I don't know if that's taboo to just do the front but at this point it seems like it's worth the try anyway. The new master cylinder/module unit is supposed to get here today. But now I'm pretty much convinced this install is over my head. I've called several shops and some mobile guys that I know but this thing is like radio active material, scary wise. I did get 2 local shops say they should be able to do it, one says he has the SPS2 programing capability. And with the battery disconnected is there supposed to be pedal resistance, mine is to the floor, then if I pump it I can get some resistance. I had a panic stop prior to this issue which may have contributed from what I read. And on the first attempt to bleed and hydraulic test the scanner listed things to look for and one was any gaps between the pad and rotors which I did notice on the RF corner and I removed the outer pad (where the gap was) cleaned it and the hardware and didn't see a gap after that but will re-check it. I read that if pushing the caliper pistons back then you're supposed to open the bleeder so as to not push fluid backwards into the abs module or it will damage it. If that's true then that's also a possibility from the previous owner having the brakes changed before I got it. I'm using an XTool ip500 scanner. Any suggestions, questions and comments welcome. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...