Cat 3406E Question! MPG Poor at 3.5-4 mpg.

Discussion in 'Ask An Owner Operator' started by rslivelyjr, Jun 18, 2024.

  1. rslivelyjr

    rslivelyjr Bobtail Member

    39
    10
    Mar 14, 2023
    0
    I have a Cat 3406E. Year 1994 . The motor is sitting in a 379 Pete. Transmission is a 15 Speed with 3.73 rears. Tires are 24.5 tall . The motor has a 550HP and 1850 Torque tune, new fuel pump , filters air and fuel . We are getting 3.5-4.0 MPG. The turbo side of things as follows , we tried running with the waste gate and without same results . Boost with the waste gate is around 30 without waste gate is around 40-42. Also truck hauls around 80-88k per load .
    Question is : We heard someone say adjust the waste gate for lower boost to get better MPG . Is this true ? What can we do to get any better numbers .more boost less boost? Thanks guys
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. Crude Truckin'

    Crude Truckin' Alien Spacecraft

    2,290
    6,016
    Oct 22, 2016
    North Dakota, Eh?
    0
    How fast you drive? Terrain? Stop and go?
     
    Deere hunter Thanks this.
  4. lester

    lester Midwest's #1 Feed Hauler

    2,861
    7,605
    Jan 2, 2012
    NW, Iowa
    0
    stock turbo?
    for fuel mileage to go up keep boost pressure down.
     
    Deere hunter and Sons Hero Thank this.
  5. rslivelyjr

    rslivelyjr Bobtail Member

    39
    10
    Mar 14, 2023
    0
    Speedlimit
     
  6. rslivelyjr

    rslivelyjr Bobtail Member

    39
    10
    Mar 14, 2023
    0
    So could adjust waste gate for lower boost pressure?
     
  7. Sons Hero

    Sons Hero Road Train Member

    1,074
    8,877
    Jan 8, 2021
    Indiana
    0
    Higher RPM, less lugging. Drivers foot can be a big part of it too. And if you run in the mountains doing a lot of stop and start. You stay local? That will hurt it too if you don’t just wind it up and hold it on the highway.
     
    Crude Truckin' and Deere hunter Thank this.
  8. rslivelyjr

    rslivelyjr Bobtail Member

    39
    10
    Mar 14, 2023
    0
    So I’m local , I run from one mill back to reload 75 miles apart . Back and forth , some hills yes but mostly 4 lane hwy, 65 limit 90% of the 75 miles . So with that Cat motor keep it in high rpm’s? Don’t let it lug at all? Because I’ve tried that before and no difference, but I’ll try again
     
  9. lester

    lester Midwest's #1 Feed Hauler

    2,861
    7,605
    Jan 2, 2012
    NW, Iowa
    0
    NO. lower your boost pressure with your right foot. Drive with your boost gauge, try and keep it down. usually with higher PRMs and no lugging
     
    cke, Crude Truckin' and Sons Hero Thank this.
  10. rslivelyjr

    rslivelyjr Bobtail Member

    39
    10
    Mar 14, 2023
    0
    But I can run high rpms and boost still at 30 that 15 speed is spread out
     
  11. lester

    lester Midwest's #1 Feed Hauler

    2,861
    7,605
    Jan 2, 2012
    NW, Iowa
    0
    take your foot out of it
     
    cke Thanks this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.