Help understanding duramaxes since I am looking for one.

Discussion in 'GM Diesel & DuraMax' started by PantheraUncia, Sep 13, 2012.

  1. PantheraUncia

    PantheraUncia Active Member 3 Years 1000 Posts


    I have been looking at duramaxes and have been looking at them online through autotrader:

    There are 31 trucks right now that meet the criteria I set in that link within 500 miles of my zipcode and I am not sure what I should be looking for as far as a good deal, bad deal, (if someone is trying to push a scam, etc).
  2. Pikey

    Pikey Moderator Staff Member 3 Years ROTM Winner 1000 Posts

    I guess because I do not know much about the duramax I would look at prices and find out what the average is for the year, miles, options that you are looking for. Then go look at some trucks, when you find one you like take it to a mechanic and have them look at it. They charge between $25-$50 for this.
  3. ChevyBoy2009

    ChevyBoy2009 Rockstar 4 Years 500 Posts

    My bro has a 08 Dirtymax CC and he loves it...the 08's have brake switch issues but its a cheap and easy fix...he paid 28k for his with 92k on it...pick one you like and go for it...i had a 01 Dirtymax and diesel got pretty expensive at 5 bucks a gallon so got rid of it...the allisons are strong runners!
  4. Sierraowner5.3

    Sierraowner5.3 Rockstar 3 Years 1000 Posts

    i dont know a whole lot, but make sure its got a allison in it!

  5. pmf608

    pmf608 Epic Member 5+ Years 1000 Posts

    As far as Duramaxes go, they all either have the Allison or a manual transmission, so you'll be good in terms of the transmission. I don't know what year you're looking for, but the 2006 and newer would probably be your best bet. I just bought a 2003 Sierra 3500 cab/chassis with a flatdeck for $4250 here with 341,000km (212,000mi) on it. One big thing to look out for on the early models (2001-2004 with RPO code LB7 in the glove box) is the injectors. They had issues with them, and they're internal injectors (under the valve covers). Therefore, it takes a lot of work (and I think about $4000 if you have a dealer do it) to change a set of injectors if they go bad. I think the late 2004-2006 (LLY code) engines had a couple of different issues, but the injectors were mounted externally so they were a lot less difficult to deal with. Overall, I'd say they were better than the first generation.

    In 2006, GM came out with the LBZ Duramax, which had more power and a 6 speed Allison instead of the 5 speed that had been used previously. The LBZ continued through 2007, when they came out with the LMM (more power,etc. and only available on the new style trucks). My understanding is that some new style trucks had the LBZ and some had the newer LMM.

    The 2011+ trucks have the LML engine in them. This engine was designed to have more power and torque and meet stricter emissions standards by adding Diesel Exhaust Fluid (urea injection into the exhaust).

    Overall, the LB7 had the least emissions stuff on it, and would probably be the simplest one. The LLY had a good mix of reliability, power, etc. The LBZ and newer have better power but more emissions crap and computer controls. I've also heard that people can get pretty close to 20 mpg on the highway easily with the LB7 and LLY (and possibly the LBZ) due to less emissions equipment, but that the newer ones with the Diesel Particulate Filters and such tend to get considerably lower fuel economy. I haven't had mine long enough to give you any personal experience on this though.

    My advice would be just make sure that whatever truck you might end up buying runs smooth, shifts smooth and doesnt have any tapping or knocking noises. As long as those areas are good, you should end up with a pretty solid truck. I can say I'm very happy with mine.
  6. PantheraUncia

    PantheraUncia Active Member 3 Years 1000 Posts

    Thanks pfm608 that was great information and helps allot
  7. aloxdaddy99

    aloxdaddy99 Rockstar 4 Years 1000 Posts

    Stay away from one that requires urea for emissions. I say this Nak cause than you are cutting into that savings we calculated the other day.
  8. Brews

    Brews Rockstar

    I found out the hard way about the injector issue with the 2001-2004. I would avoid them.
  9. LB'07-Z

    LB'07-Z Rockstar 100 Posts

    I wouldn't shy away from an 01-04 if the injectors have been replaced. Thats why I just bought my 02. The dealership i bought mine from had records that the previous owner had them replaced a year and a half ago. You also can take one to a Chevy dealer and have them test the injectors. I'vealso heard of the 03-05 having overheating issues while towing due to the hood design. If you will notice on the 05.5-07 classic the hood is alittle taller and allows the engine to cool easier. I went with the 02 mainly because I was on a budget and have wanted a Dmax for a long time but if money hadn't have been no object I personally would have got an 05.5-07 classic mainly because I like that body style.
  10. PantheraUncia

    PantheraUncia Active Member 3 Years 1000 Posts

    Yep, I am going to do my best to stay away from a brand new one so I don't have to deal with the urea mess.... I think a 2010 will be the newest i am looking at.

    - - - Updated - - -

    So this brings up a good question that I would like an answer to. The fuel injectors on my gasser (5.3L) are about $100 each or $800 all together + install unless I do it myself.

    What is the cost (if you are out of warranty) on the injectors on a Duramax? I keep hearing something like $4000 installed? is it really that high? can you do it yourself? and what is the life expectancy of them?

Share This Page

Newest Gallery Photos