Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!


  1. General Discussion
    I just bought a 13 lml. 155,000 miles. Test drove it all sounded great. After about 300 miles I started hearing a knock, hooked computer up and cylinder 6 balance rate was at -4.2. Changed injector same problem. The noise only comes when the truck it warm or up to temp. I can unplug injector...
  2. 911 Problems Forum
    I have a 2008 gmc 2500 just had a ppe stage 5 trans and convert put in a year ago. About 2 weeks ago I had a minor tick that would get louder with rpm and I was driving home from work and its now really bad. I have taken the transmission out to check the flex plate and still all in 1 piece...
  3. 06-07 LBZ & LLY Duramax Powertrain
    Got a knock and black smoke on acceleration balance rates are between -3 and 3 pretty sure its all stock i know i havent done anything to it what should i b checking i checked all boots for a boost leak
  4. General Discussion
    I need help with my duramax. It’s a 2003 GMC Sierra 2500hd. I started rolling coal one day (stock truck) and with the already hazy exhaust smoke, I knew that I had dropped an injector. I let my dad test drive it and he must have pushed it past the edge as it starts knocking and blowing out...
  5. 04.5-05 LLY Duramax Powertrain
    My truck has been leaking coolant and started knocking td I think it could be the injectors but I have no clue
  6. 01-04.5 LB7 Duramax Powertrain
    I installed a new set of injectors on my LB7 and after I put everything back together I could hear a slight knock. I ask a couple of guys and they told my that it sounds normal. I took the truck on a 150 mile trip and when i got home the knock was louder. I notice that I was getting white...
  7. 01-04.5 LB7 Duramax Powertrain
    After my truck has sat all night at work I start it up to head home...and there is a very noticable knock for about the first five minutes or so of driving. Any ideas?
  8. 01-04.5 LB7 Duramax Powertrain
    hey everybody. i recently got this dmax lb7 and i was told that the injectors were replaced around 20000 miles ago. it is a retired formans truck from a local company here near me. anyways, i noticed a knock upon crusing speeds, so i took it the the dealership in hopes of getting new...