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Discussion Starter · #1 ·
What makes the injectors go bad in these trucks? Are they hard to remove/install?
 

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From what I have read it is almost from "sandblasting" effect. They mostly start to leak fuel into the crankcase (at least on the 01-04 LB7). As far as changing them out.....if your truck is an 01-04 LB7 (8th digit of the vin is a 1), they are a pain to change since you have to remove the valve cover. Normally when they get replaced, you change at least 4 of them, but I would change all 8 since the truck will have to be torn apart quite a bit. If you have one of the newer truck 04 LLY and newer (8th digit of vin is either a 2 or D) they are pretty easy to change since you don't have to take the valve cover off and you can change them one at time.

Also, could you help us out by filling in a signature? Even though you posted in the LB7 section, I don't always trust that...thanks Signature
 

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I am looking to buying a 01LB7 right now, I am just asking plenty of question so I am not blind sighted like I was when I bought my Dodge(24V Cummins has been my worse nightmare) I have changed the injectors on my dodge by removing the valve cover it was not to bad.
 

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From what I read on other forums, it takes a good 3-4 hours just to get to the injectors...I think they said it takes a couple of days at a dealer. There was a reason why GM made the policy to change all 8 at one time.
 

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Hello

I am picking apart my enginge now to get to the injectors, looks like the valve cover is two parts. Do I need to remove the lower bolts or the upper ones? Getting my injectors tomorrow so I wantet to take them out so everything would be ready today.

Thanks
 

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Hello

I am picking apart my enginge now to get to the injectors, looks like the valve cover is two parts. Do I need to remove the lower bolts or the upper ones? Getting my injectors tomorrow so I wantet to take them out so everything would be ready today.

Thanks
keep us informed as it looks like i will be doing the same here pretty quick
 

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I have the same problem. The dealer told me 18 hours of labor and yes I'm pretty sure you have to take both off to get to them here is a step by step post of how too..



http://www.duramaxforum.com/forum/how-tos-diy-write-ups/44139-how-change-lb7-injectors-pictures.html

Hey,

After I changed mine I have done eight cars here in Norway. When I work really fast I would do it in about eight hours.

The only thing I can see that is "problems" is some of the bolts are hard to get to but with right tools no problem. The other thing is that the injectors are really hard to get loose some times. Every time I am thinking about making a special tool for this but its out of my mind when I am done :D
 

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It really depends on your set up if you have the potential for aftermarket and if you dont GO STOCK, but it ranges from 1500 to id say the most exspensive 2200. it also depends on were you get them

Dealer prices will be higher.
 

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How much are 8 inj's???????
I just paid a Chevy dealer $4,570 to replace all 8 in my 02. That included oil change, disposal fee, taxes,etc.:mad:
 

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What makes the injectors go bad in these trucks? Are they hard to remove/install?
From what I have gleaned after owning an 02 for a year and a half, the cause of the bad injectors is a faulty design on GM's part, which is why they came out with the recall. Others can interject their thoughts here also (but it is my understanding that the injectors usually go bad on the Duramax's around 150,000 miles with normal usage). I also hear that certain things can extend the life of the injectors, or decreasing the chance of failure, like lift pumps "more specifically not getting into a situation where your fuel pressure is low at the injectors", running fual addatives that lubricate the injectors and things like this.

If you are looking for the symptoms of injectors going bad I think there are two main ones, most common seems to be fuel in the crank case, and I think ankother one is excessive smoke from the exhaust. Again, hopefully some of the other guys on here can weight in on this because a lot of them have much more experience than I but hopefully this helps out.

Good Luck, and you will LOVE your DM
 

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From what I have gleaned after owning an 02 for a year and a half, the cause of the bad injectors is a faulty design on GM's part, which is why they came out with the recall. Others can interject their thoughts here also (but it is my understanding that the injectors usually go bad on the Duramax's around 150,000 miles with normal usage). I also hear that certain things can extend the life of the injectors, or decreasing the chance of failure, like lift pumps "more specifically not getting into a situation where your fuel pressure is low at the injectors", running fual addatives that lubricate the injectors and things like this.

If you are looking for the symptoms of injectors going bad I think there are two main ones, most common seems to be fuel in the crank case, and I think ankother one is excessive smoke from the exhaust. Again, hopefully some of the other guys on here can weight in on this because a lot of them have much more experience than I but hopefully this helps out.


Good Luck, and you will LOVE your DM


The injectors are not designed by GM, they are made by bosch. The original duramax engine was designed by isuzu in japan and had all DENZO fuel system parts. Denzo makes all kinds of parts for japanese crotch rockets and are very good parts. When GM bought the duramax form Isuzu, they changed the design to use bosch fuel system parts and that's where the problem started. I was told by different reps that the original DENZO/DURAMAX engines in japan dont have these fuel in oil and smoking problems. Now you know why GM went belly up, desicions like that.
 

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From what I have gleaned after owning an 02 for a year and a half, the cause of the bad injectors is a faulty design on GM's part, which is why they came out with the recall. Others can interject their thoughts here also (but it is my understanding that the injectors usually go bad on the Duramax's around 150,000 miles with normal usage). I also hear that certain things can extend the life of the injectors, or decreasing the chance of failure, like lift pumps "more specifically not getting into a situation where your fuel pressure is low at the injectors", running fual addatives that lubricate the injectors and things like this.

If you are looking for the symptoms of injectors going bad I think there are two main ones, most common seems to be fuel in the crank case, and I think ankother one is excessive smoke from the exhaust. Again, hopefully some of the other guys on here can weight in on this because a lot of them have much more experience than I but hopefully this helps out.

Good Luck, and you will LOVE your DM
I have 180,000 miles on my DMax and I'm still running factory injectors. I add a can of Sea Foam to clean the injectors every 4 or 5 tanks, which you should do with any diesel. I also change my fuel filter every 4,000 - 6,000 miles.

It all boils down to luck of the draw, and maintenance... there's no "magic additive," or "magic bolt-on item" that is going to make your injectors last longer.

Added: By the way... a very wise man once told me, "Never believe anything you hear, and only half of what you see."
 

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Anyone know where I can get a reasonable priced set of Injectors for 04 LB7 as GMC are saying they will not cover them under THEIR warranty even though it falls under the criteria of THEIR TB, I have been around with them and my local dealership. Trying to deal with GMC is a pain in it's self as the "customer service" don't speak English and they won't put you through to a person in the States.
So if anyone has any idea where I can get a set of Injectors, please let me know it would be greatly appreciated.

Thanks
 

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www.lincolndiesel.webs.com


Thats the cheapest place i could find. Month or so wait from them right now though. I ended up getting mine at the dealer just because i needed them quick and he matched the best price i could find anywhere else that had them in stock ($2150).
 
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