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redwngr last won the day on March 15 2016

redwngr had the most liked content!

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About redwngr

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  1. Lights on trailer working correctly and without flicker? Are posts and pins on connectors clean/corrosion free?
  2. C/K, you are correct. I must have been thinking about powder coat rather than e-coat. https://www.sharrettsplating.com/blog/e-coating-vs-powder-coating/
  3. Dipping in wax gets the coating on the inside of the frame as well. Not sure how easy it would be to get e-coat coverage on the inside. (no saying impossible, but wondering what the process would be)
  4. From a post of mine on another forum: Small section of the info available in the GM upfitter manuals: Charging System Operation The purpose of the charging system is to maintain the battery charge and vehicle loads. There are 6 modes of operation and they include: • Battery Sulfation Mode • Charge Mode • Fuel Economy Mode • Headlamp Mode • Start Up Mode • Voltage Reduction Mode The engine control module (ECM) controls the generator through the generator turn ON signal circuit. The ECM monitors the generator performance though the generator field duty cycle signal circuit. The signal is a pulse width modulation (PWM) signal of 128 Hz with a duty cycle of 0–100 percent. Normal duty cycle is between 5–95 percent. Between 0–5 percent and 95– 100 percent are for diagnostic purposes. The following table shows the commanded duty cycle and output voltage of the generator: Commanded Duty Cycle ....Generator Output Voltage ...............10% ......................11 V ................20% .....................11.56 V ................30% .....................12.12 V ................40% .....................12.68 V ................50% .....................13.25 V ................60% .....................13.81 V ................70% .....................14.37 V ................80% .....................14.94 V ................90% .....................15.5 V The generator provides a feedback signal of the generator voltage output through the generator field duty cycle signal circuit to the ECM. This information issent to the body control module (BCM). The signal is PWM signal of 128 Hz with a duty cycle of 0– 100 percent. Normal duty cycle is between 5– 99 percent. Between 0–5 percent and 100 percent are for diagnostic purposes. Battery Sulfation Mode The BCM will enter this mode when the interpreted generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements. Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met. • The wipers are ON for more than 3 seconds. • GMLAN (Climate Control Voltage Boost Mode Request) is true, as sensed by the HVAC control head. High speed cooling fan, rear defogger and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. • The estimated battery temperature is less than 0° C (32°F). • Battery State of Charge is less than 80 percent. • Vehicle speed is greater than 145 km/h (90 mph) • Current sensor fault exists. • System voltage was determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature. Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 amperes and greater than −8 amperes, and the battery state-of-charge is greater than or equal to 80 percent. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present. Headlamp Mode The BCM will enter Headlamp Mode when ever the headlamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V. Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 seconds. Voltage Reduction Mode The BCM will enter Voltage Reduction Mode when the calculated ambient air temperature is above 0°C (32° F). The calculated battery current is less than 1 ampere and greater than −7 amperes, and the generator field duty cycle is less than 99 percent. Its targeted generator output voltage is 12.9 V. The BCM will exit this mode once the criteria are met for Charge Mode. Instrument Panel Cluster Operation Charge Indicator Operation The instrument panel cluster illuminates the charge indicator and displays a warning message in the driver information center if equipped, when the one or more of the following occurs: • The engine control module (ECM) detects that the generator output is less than 11 V or greater than 16 V. The instrument panel cluster receives a GMLAN message from the ECM requesting illumination. • The instrument panel cluster determines that the system voltage is less than 11 V or greater than 16 V for more than 30 seconds. The instrument panel cluster receives a GMLAN message from the body control module (BCM) indicating there is a system voltage range concern. • The instrument panel cluster performs the displays test at the start of each ignition cycle. The indicator illuminates for approximately 3 seconds.
  5. Just like the 6.6 dmax, the turbo, scr and dpf make it quiet enough that there is no muffler or resonator. On the 6.6 the emission stuff is under the truck. On the 3.0 it's in the engine bay. Visual inspection will require opening the hood....
  6. Video interview of one of the GM engineers suggested part of it is better aerodynamics on the silvy. The other part is the way the tests are done. EPA requires that if an option is purchased on a certain % of vehicles that the impact (weight?) of that content be included in the testing. Sierra's, on average, have more added content and/or higher trim -- and that impacts the epa rating.
  7. The alternator output is controlled by the computer. It is NOT a simple voltage regulator like what controlled alternators for many years. Output is varied base on many of the items that the computer is able to monitor. There is a multipage write-up / explanation in the GMupfitter documents.
  8. Has it had the brake/abs recalls/updates completed?
  9. https://www.gmfleetorderguide.com/NASApp/domestic/rpocodes.jsp?year=2020&regionID=1&lang=1&divisionID=1&vehicleID=21795
  10. Of course there is no way to now if the one you find on a lot has already been repaired..... Do an inspection after it is repaired, and then make a decision.
  11. Silverado reg cab only available in WT trim Sierra reg bab only available in 'Sierra' trim, with is the base trim similar to chev's WT. Both only in long box (8ft) . 4.3L is standard, 2.7L is available, 5.3L is available -- it's the older AFM motor (L82), not the newer DFM motor (L84) that is in all the other trims. No start/stop, unless it has the 2.7 L82 can have Flexfuel capablity added (rpo FHS ) Standard seats are the 40/20/40 no storage Storage version comes on and is only available with the 2.7L
  12. It's to make it's easier to slide under to drain oil and change filter without having to use a jack/lift. Grill is taller (on HD's) to permit the larger diameter fan and taller radiator needed to get the cooling required to obtain the higher tow ratings in the SAE test. The larger fan also resulted in the new separate belt to drive just the fan. Yes, it seems like this is the one that creates the idle 'thump' noise.
  13. Not sure what year was first for HD's, but 2018 HD has it. I'm gonna guess it started with the changes made for the L5P, model year 2017.
  14. Bonus is that turning tow/hail on also disables the auto stop/start. From; https://gm-techlink.com/?p=12048 3.0L Diesel Engine The diesel exhaust brake function on the 3.0L diesel engine is part of the Tow/Haul Mode Grade Braking system. Tow/Haul Mode Grade Braking is only enabled while the Tow/Haul Mode is selected. On vehicles equipped with Driver Mode Control, Tow/Haul Mode can be activated/deactivated by turning the Driver Mode knob to the left. (Fig. 11) When selected, the Tow/Haul Mode symbol will illuminate in the instrument cluster. Fig. 11 If the vehicle is turned off with Tow/Haul Mode active for less than four hours, Tow/Haul will remain active after the vehicle has been turned on again. Otherwise, the vehicle will start in Normal Mode. For vehicles without Driver Mode Control, press the Tow/Haul button on the center of the instrument panel. TIP: The Automatic Engine Stop/Start system is unavailable when the Tow/Haul Mode is active.
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