6.6L Duramax Deisel

I got a noticeable mileage increase after doing the lift pump and injectors, from 12 to 14. Mechanic said the double filtration is a good idea in any diesel to make injectors last, not just the LB7. 1K is a small price to pay if he is correct.

04.5 LLY CCSB 4x4 towing 10,000lbs all over the west coast. 125K miles. ZERO engine transmission issues, very reliable, comfortable. Even towing steep grades I haven't had any of the overheating issues that are claimed problems with the LLY.

use diagnostic reader to read the injector trim values at every oil change to track them. Very little change since new, and WELL within the factory normal range at idle.

Been anal about changing fuel filters and added a secondary fuel filter.

The only thing that has failed are the front wheel bearings. Easy 1 hr fix and timken upgraded replacements available on amazon for about $100 each.

Probably be passing it on to our son this year and get the 2015 2500HD Duramax that is just being shipped.

NHIrish wrote:

mockturtle wrote:
Thanks, all, for the valuable input.

Be careful as some of it wasn't so valuable.

The duramax is a very good engine. Some model years had issues with one thing or another, just like others. All diesels (all engines) are water sensitive and both Ford and Chevrolet are using injectors designed for European spec fuel, which is of higher quality than US fuel. As a result, there are some injector and hpfp issues due to a lack of lubricity...and some people (like me) try to avoid issues by using fuel additives.

None of the big three is bad, all have an issue or two here or there and some are more prone to certain issues than others. When considering what to buy, look at the whole package and buy what works best for you in terms of engine, transmission, payload etc etc.

3 sets of injectors so far on mine, in first 100k (including originsls) one done under warranty. When number 3 came up, the independant Mechanic recommended a FASS lift pump double filtration system to avoid this 4000 dollar job from having to be done again anytime soon. it removes water, vapour and particles down to 3 microns. The standard filter is good for 8-10 microns. The injectors are not rated for particles that big. He also said I will notice a boost in mileage.

Opti-lube XPD is better for lubricity than stanadyne. After using Stanadyne since new, I am going to try a switch.

study

This is also informative. I hope I have saved somebody else from a large repair bill.

duramax injector myth

calamus wrote:
2003 bought new 109,000 miles no problems till last year had to put injectors in. It should of been a recall IMO since they extended the warranty to 200,000 or 7 years we were out on years. But I will never buy another GM after the experience we had with them.

What do you plan to buy that will give you more than 7 years or 200k??

calamus wrote:
2003 bought new 109,000 miles no problems till last year had to put injectors in. It should of been a recall IMO since they extended the warranty to 200,000 or 7 years we were out on years. But I will never buy another GM after the experience we had with them.

Just making sure I'm reading this right. You had no problems with the truck for 10 years but you'll never by another because of the experience?
Really?
I don't know, that seems pretty good to me.

rodeoboy wrote:
Mine is a 2005 and I like it. No issues yet. I pull a 15000 Lbs 5th wheel and get around 11 MPG.

Rodeoboy

same for us. No reason for trading it for anything else.

chevman

Had an 07 2500 HD traded for a 11 2500HD wish I had the 07 back. Had more than my share of trouble with the DEF. Milage was way better than I get now. And gm said I would get better than the 07. Wrong. Just yesterday I was going along and the chime rang and the DIC said DEF low. range 1150 miles. Really? thats almost 2 gal's left in the tank. POS.

Nobody has mentioned the good hardly.

Best year was the 2006-2007(Classic). It came with the LBZ motor, which was the most powerful before all the EPA******went on and killed fuel economy. Can get 20mpg unloaded.

Then they went to the LMM (I have). Fuel economy hurt some due to the DPF (diesel particulate filter). I get about 16-18 unloaded. Still good motor.

The LLY from 2004-2005 is a good motor. My parents have one and have never had an issue out of it and have about 70k on it.

Before then, there were injector issues as others have stated.

I would look for one 2005+. The 2005 has the 5-speed allison tranny where as the 2006+ have the 6-speed Allison.

Duramax is my favorite motor as they really haven't had to make a major overhaul of the engine itself as Ford and Dodge have done over the past 10+ years.

The best advice is to only buy a diesel if you need a diesel...if I could have a gas engine and tow my fifth wheel I would. Diesel just much more expensive.

mockturtle wrote:
Thanks, all, for the valuable input.

Be careful as some of it wasn't so valuable.

The duramax is a very good engine. Some model years had issues with one thing or another, just like others. All diesels (all engines) are water sensitive and both Ford and Chevrolet are using injectors designed for European spec fuel, which is of higher quality than US fuel. As a result, there are some injector and hpfp issues due to a lack of lubricity...and some people (like me) try to avoid issues by using fuel additives.

None of the big three is bad, all have an issue or two here or there and some are more prone to certain issues than others. When considering what to buy, look at the whole package and buy what works best for you in terms of engine, transmission, payload etc etc.