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Sounds like a failed injector and holed piston. If that is the case it should be repairable. Sorry to hear. What was your additive use history?
 

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I think America's "dry" ultra low sulfur diesel fuel is killing diesel engines. We have more problems with injectors and high pressure pumps than other countries do. Yes, this is by Hotshots Secret, who wants to sell additive (good additive I think) but I don't think they are wrong. The "CP4 debacle" high pressure fuel pump issue was much more prevalent here in America than Europe.

 

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I think America's "dry" ultra low sulfur diesel fuel is killing diesel engines. We have more problems with injectors and high pressure pumps than other countries do. Yes, this is by Hotshots Secret, who wants to sell additive (good additive I think) but I don't think they are wrong. The "CP4 debacle" high pressure fuel pump issue was much more prevalent here in America than Europe.

Our diesel in Canada is as dry as yours. But I bet you don’t see an injector failures with the 2019 and up trucks. That’s the only reason GM changed to a higher pressure injector. They were looking for a way to stop warranty claims that cost them an engine.
But I hope you are right and I am wrong.
I been using Hotshots since new. I actually use a double dose. And keep my fingers crossed……
Actually the CP4 has a design flaw. A big one. These pumps have a roller that rides on a cam. The CP4 that I saw had nothing to keep the roller straight. Or square and rolling on the cam and over the lobe. They are prone to turning 90 deg to the lobe on the cam. That left the roller sliding sideways on the cam and over the lobe. Metal shavings from the roller ended up all through the system.
I didn’t see any actual wear from normal use. Just from the roller being 90 deg out. Eventually causing a flat spot on the roller and damage to the lobe.
I bet the idiot that designed it never thought it would twist sideways as long as there was pressure keeping it rolling on the cam and lobe. The roller being fairly wide would stay true to the the cam.
Makes me wonder if high RPM caused it to bounce over the lobe and that aloud it to turn sideways and eventually destroy itself…
Any thoughts.
 

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I think America's "dry" ultra low sulfur diesel fuel is killing diesel engines. We have more problems with injectors and high pressure pumps than other countries do. Yes, this is by Hotshots Secret, who wants to sell additive (good additive I think) but I don't think they are wrong. The "CP4 debacle" high pressure fuel pump issue was much more prevalent here in America than Europe.

ULSD is global now, but maybe other countries have more additives for lubricity. I'm pretty sure they have higher cetane numbers in general.

That said, research into the CP4.2 failures has revealed that it's actually a design flaw with the CP4.2 itself and has nothing to do with ULSD or lack of lubrication. The problem is that the pistons aren't keyed in any way and over time they can rotate, this causes the pump to eat itself alive because the rollers are now perpendicular to the rotation of the cam.
 
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ULSD is global now, but maybe other countries have more additives for lubricity. I'm pretty sure they have higher cetane numbers in general.

That said, research into the CP4.2 failures has revealed that it's actually a design flaw with the CP4.2 itself and has nothing to do with ULSD or lack of lubrication. The problem is that the pistons aren't keyed in any way and over time they can rotate, this causes the pump to eat itself alive because the rollers are now perpendicular to the rotation of the cam.
Exactly
I couldn’t believe it when I saw it. A glaring oversight…..
Bicycle part Auto part Machine Font Engineering
 

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Thanks for the CP4 info! I recall reading awhile ago the whole mess is in litigation.

High pressure pump failures (typically announced by loud ticking) have occurred in our 2.8s, but they seem fairly rare. It would be interesting to see how our Denso pumps are designed.
 

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Thanks for the CP4 info! I recall reading awhile ago the whole mess is in litigation.
Yup, and for the EcoDiesel there is actually a recall for the CP4.2 now, however there is no fix yet. The recall was announced maybe a couple of months ago as we got a notice in the mail for my wife's Jeep EcoDiesel. They're working on a permanent fix rather than just replacing existing CP4.2 pumps with new ones with the same flaw. It will be interesting to see what the fix ends up being.

High pressure pump failures (typically announced by loud ticking) have occurred in our 2.8s, but they seem fairly rare. It would be interesting to see how our Denso pumps are designed.
I think I heard/read somewhere that the ticking isn't the pump portion itself but rather an issue with a valve or regulator? I'd have to search, but I think ultimately it was something that wouldn't result in catastrophic failure like the CP4.2. Apparently it's also something that can't be replaced and the whole pump has to be replaced to address it. I'm a bit fuzzy on the details, but that's what I remember.
 
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I have a very early 2016 Colorado DMax 167K miles. Had no issues whatsoever until 9,000 miles after the dealer replaced my timing belt and water pump. Tensioner broke (cracked down the middle of the tensioner , stretched the belt, piston / valve contact on all 4 cylinders (broke all the exhaust rockers) Naturally because GM doesn't require replacing the tensioner they say I'm on the hook for the new long block. I call BS, something happened while they were in there as tensioners don't just break. So they either over clocked it or over tightened it.
 

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I have a very early 2016 Colorado DMax 167K miles. Had no issues whatsoever until 9,000 miles after the dealer replaced my timing belt and water pump. Tensioner broke (cracked down the middle of the tensioner , stretched the belt, piston / valve contact on all 4 cylinders (broke all the exhaust rockers) Naturally because GM doesn't require replacing the tensioner they say I'm on the hook for the new long block. I call BS, something happened while they were in there as tensioners don't just break. So they either over clocked it or over tightened it.
Does the dealer provide any sort of warranty on their work? Unbelievable that they didn't replace the tensioner while in there. What a drag - they took a good running 2.8 that did not display the problems so many have had in this thread and they basically wrecked it. That is maddening.

Not looking forward to the job, but I plan to do the timing belt myself when it gets there. Have done it on other engines, it always sucks. There will be bloody knuckles...
 

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Does the dealer provide any sort of warranty on their work? Unbelievable that they didn't replace the tensioner while in there. What a drag - they took a good running 2.8 that did not display the problems so many have had in this thread and they basically wrecked it. That is maddening.

Not looking forward to the job, but I plan to do the timing belt myself when it gets there. Have done it on other engines, it always sucks. There will be bloody knuckles...
Agreed, ridiculous.... they didn't even offer the tensioner. I work on the big stuff for a living (Detroit, Cummins, Caterpillar, Freightliner and Western Star etc.) I was relying on their expertise as a light duty automotive dealer. Next time I'll do it myself.
They supposedly carry a 2 year unlimited mileage warranty but were very quick to dismiss it as a parts or workmanship issue. "failed part that we didn't replace - your problem, here's 20% off of $9600 for your trouble"
 

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Agreed, ridiculous.... they didn't even offer the tensioner. I work on the big stuff for a living (Detroit, Cummins, Caterpillar, Freightliner and Western Star etc.) I was relying on their expertise as a light duty automotive dealer. Next time I'll do it myself.
They supposedly carry a 2 year unlimited mileage warranty but were very quick to dismiss it as a parts or workmanship issue. "failed part that we didn't replace - your problem, here's 20% off of $9600 for your trouble"
I would make a fuss. Recently got the stonewall treatment from Genworth on my 93 year old mother's long term care insurance claim. I have worked in claims for 34 years, so after getting blown off by the "little people" I looked him up and sent an email directly to the General Counsel of Genworth corporate. It was calmly and factually written, and it outlined the Colorado insurance statutes they were in violation of, and it gave a timetable outlining what I planned to do about it.

Heard back from the GC within an hour, and my mother's LTC claim was accepted. Amazing how that works! FYI, if not familiar, the General Counsel is a large corporation's top attorney that reports directly to the CEO. Rattling the GC's cage was a baller move on my part, if I don't say so myself ;)

Don't deal with the little people. Take this up the chain...
 

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I would make a fuss. Recently got the stonewall treatment from Genworth on my 93 year old mother's long term care insurance claim. I have worked in claims for 34 years, so after getting blown off by the "little people" I looked him up and sent an email directly to the General Counsel of Genworth corporate. It was calmly and factually written, and it outlined the Colorado insurance statutes they were in violation of, and it gave a timetable outlining what I planned to do about it.

Heard back from the GC within an hour, and my mother's LTC claim was accepted. Amazing how that works! FYI, if not familiar, the General Counsel is a large corporation's top attorney that reports directly to the CEO. Rattling the GC's cage was a baller move on my part, if I don't say so myself ;)

Don't deal with the little people. Take this up the chain...
 

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Looks like the sales department at said dealership wants to try to "make this right" if things go well I should be driving out of there today with a '22 3.0L RST Sliverado. Trying to keep it diesel due to my lengthy commute. The sales manager at our dealer group took delivery of a '22 3.0L Sierra Denali a couple of months ago and running 31-37 MPG. EPA estimates are way under actual. That kind of economy is right up my alley since I average around 2k miles a month.
 

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Looks like the sales department at said dealership wants to try to "make this right" if things go well I should be driving out of there today with a '22 3.0L RST Sliverado. Trying to keep it diesel due to my lengthy commute. The sales manager at our dealer group took delivery of a '22 3.0L Sierra Denali a couple of months ago and running 31-37 MPG. EPA estimates are way under actual. That kind of economy is right up my alley since I average around 2k miles a month.
Nice! A friend has a Sierra with the 3.0, he has about 50K miles on it now and loves it.
 
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