Chevy and GMC Duramax Diesel Forum banner


  1. Speedometer showing Zero - Electrical / computer / sensor - Coincidence or growing problems

    06-07 LBZ & LLY Duramax Powertrain
    Ok sorry for the wall of text, but there is a lot of info for my problems, Thank you for reading. So I posted a few days ago about an oil leak on the passenger side and found that there was a fair amount of oil pooled in the ERG cooler. After it all drained out and I re-tightened the bolts to...
  2. After Jumpstart Speedometer Reading Wrong

    Gauges, Electronics and Wiring.
    After, I had left the ignition on and ran the battery down. I had to jump it off, of course. Now the speedometer, max's out to 85 and I assume the governor kicks in. The truck thinks I'm doing 85mph, but the fast as it will go is 37 mph. I know this by GPS, I disconnected the batteries...
  3. Speedometer reading random MPH

    Gauges, Electronics and Wiring.
    For a while now my speedometer has been reading random speeds, it started by reading 20mph above my actual speed, and now it's pretty much stuck on 120mph. from time-to-time, it would read the correct speed, but it was a crap shoot if it was right everytime I drove my truck down the road...