L
Motor codes
In the 800 platform the LB7 was the first Duramax motor code. It had a problem with internal fuel injectors that where big $$ to replace because of the labor time. Then mid 04 came the LLY with external injectors and a few other updates (hp and ex). Both had 5 sp allisons. In 06 came the LBZ along with a 6sd allison. It has 630 something fpt. I think the 2006 and the 2007 (classic) are the two best years for performance and towing. In mid 2007 came the 900 platform and the particle filter. The truck its self is better in many ways but our wonderful government made all diesels manufactured for highway use have particle filter systems. That added over a thousand dollars to the cost of the diesel option, made it lack in performance, lack in mpg, can not let it idle it for a long time, can only burn low sulfur fuel, and the list goes on. You can throw a aftermarket exhaust system on it and get rid of the filter but it will cost you your warranty. To replace the filter its to the tune of over a thousand dollars. If you can't tell I'm a little sore on that subject. So in conclusion if you looking for a used truck I would go with a 2006 to mid 2007. (IMO) Good Luck! Jay
In the 800 platform the LB7 was the first Duramax motor code. It had a problem with internal fuel injectors that where big $$ to replace because of the labor time. Then mid 04 came the LLY with external injectors and a few other updates (hp and ex). Both had 5 sp allisons. In 06 came the LBZ along with a 6sd allison. It has 630 something fpt. I think the 2006 and the 2007 (classic) are the two best years for performance and towing. In mid 2007 came the 900 platform and the particle filter. The truck its self is better in many ways but our wonderful government made all diesels manufactured for highway use have particle filter systems. That added over a thousand dollars to the cost of the diesel option, made it lack in performance, lack in mpg, can not let it idle it for a long time, can only burn low sulfur fuel, and the list goes on. You can throw a aftermarket exhaust system on it and get rid of the filter but it will cost you your warranty. To replace the filter its to the tune of over a thousand dollars. If you can't tell I'm a little sore on that subject. So in conclusion if you looking for a used truck I would go with a 2006 to mid 2007. (IMO) Good Luck! Jay
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