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Discussion Starter · #1 ·
Just curious if anyone has any knowledge on how long I can expect to go on factory injectors in an LML? I just rolled 180,000mi, use Opti-lube red or purple every tank, and my balance rates are typically +/-1.0 or better (occasionally I may see 1.5 or so but it always gets better). Just wondering when it will be time to flow test them. I know diesels get louder with age, but I feel like my injectors are really loud around 1500rpm in lower gears (before TC locks).
 

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I know of guys over 240k miles on stock injectors. If balance rates, and return rates are good, dont worry about them. Most people will lift the head or crack a piston before they have the injectors go bad.
 

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Discussion Starter · #3 ·
I know of guys over 240k miles on stock injectors. If balance rates, and return rates are good, dont worry about them. Most people will lift the head or crack a piston before they have the injectors go bad.
Well thats good to know. I really don't plan to lift the heads and I definitively don't want to crack a piston lol. I don't have a way to check return rates, I don't think. I was mostly starting to think about it because I notice how much louder they are around 1500rpm, but only 1-4 gear before TC locks, compared to the rest of the RPM range.
 

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When checking the return rates you run the return lines into a cup or bottle for 15 second intervals and measure how much in ML. Youd have to look the acceptable range for an lml. I know the older years it was like 4ml per 15 seconds an injector
 

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Discussion Starter · #5 ·
When checking the return rates you run the return lines into a cup or bottle for 15 second intervals and measure how much in ML. Youd have to look the acceptable range for an lml. I know the older years it was like 4ml per 15 seconds an injector
Yeah that sounds like something I won't check unless there is an obvious sign of a problem lol. What would bad return rates result in? What are the symptoms?
 

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Bad return rates are bad injectors. Sometimes you'll have symptoms of bad injectors when balance rates arent that bad but then you'll have high return rates.
 

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Discussion Starter · #7 ·
Bad return rates are bad injectors. Sometimes you'll have symptoms of bad injectors when balance rates arent that bad but then you'll have high return rates.
Oh okay. So the typical symptoms like a knock or white smoke? Why do injectors get louder with age? Just from getting worn?

Thanks for all the info btw
 

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Youre welcome that's what were all here for. Yeah typical symptoms white smoke, raw fuel smell, knock, bad balance n return rates. Idk if injectors get louder with age or not. I've been around high mileage trucks with the original injectors and they didnt seem to be any louder.
 

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They any louder chevor? I bet not
 

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The new injection pump is loud compared to my other 2013 that had 84k.

IDK injectors make noise?
 

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Discussion Starter · #12 ·
They any louder chevor? I bet not
Heck I may just be hearing engine noise or exhaust? I've just heard that diesels get louder with age and I know mine sure seems like it has. I assumed it was injector noise but may just be engine noise :gearjamin
 

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Discussion Starter · #13 ·
Stock injectors still at over 660k in my 2013. Stock Injection pump wore out 595k.
Thats really awesome! Hope I can get that many miles out of my truck
 

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Usually these trucks dont have issues with it but maybe the valve lash needs tightened up
 

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Discussion Starter · #15 ·
Usually these trucks dont have issues with it but maybe the valve lash needs tightened up
I kinda feel like all (newer diesels at least) get louder with age. I would think if it was something with the valves, there would be noise all the time, or maybe increase with RPMs. But hell I am no mechanic. Unless there is an obvious sign of a problem, I just plan on driving it. I just thought I remembered reading that injectors don't last much longer than 200,000mi, but that may have been for a different gen duramax.
 

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The pump in mine is sure loud, I don't recall the pumps in my 2008 Sierra and 2012 silverado being this loud, but I didn't have as many miles on them that I do now. It almost sounds like the typical loud GM pumps from the 90s in the cars and trucks. The injectors are definitely loud at 190,000 miles on mine.
 

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Discussion Starter · #17 ·
The pump in mine is sure loud, I don't recall the pumps in my 2008 Sierra and 2012 silverado being this loud, but I didn't have as many miles on them that I do now. It almost sounds like the typical loud GM pumps from the 90s in the cars and trucks. The injectors are definitely loud at 190,000 miles on mine.
I guess I don’t know what the injection pump sounds like? Can you describe it?

And at 180,000mi, my truck is without a doubt louder than it once was. It had 60,000mi on it when I bought it, and it was so quiet my brother didn’t even know it was a diesel. Well there is no mistaking it now lol.
 
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