I recently bought a 2013 Silverado 2500 HD. The next day, the guy that did a bunch of work on my previous LBZ told me about CP4 issues, saying it was not a question of if it would fail, but a question of when it would fail. Since then, the Chevy dealer I bought it from and a diesel shop fellow have both told me they have never known of one that failed. Id like to hear from some of you about this. Are there any things I can do to help prevent problems? Thanks.
CP4 Issues
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search is your friend. yes they fail. no you cant stop it unless you do a cp3 swap and get a tune for it.
Like James said, "search and you shall find". I would also agree with James in the fact that it isn't a question of if but when. The only sure fire solution is to put a CP3 in it's place, be it one that requires an emissions compliant tune or one of the few "no tuning required" kits.
The part that is hard to swallow is the inconsistency of them, some fail early some go hundreds of thousands of miles, they are just an unknown duration ticking time bomb IMO.
The part that is hard to swallow is the inconsistency of them, some fail early some go hundreds of thousands of miles, they are just an unknown duration ticking time bomb IMO.
The dealer and the shop apparently don’t know their ass from a hole in the wall. Like James said yes they fail and it’s more when than if. I do know some people that have had good luck with them, but they are extremely anal about filter changes and making sure their water separator stays drained. From what I’ve read, they fail because of lack of lubrication. Causing it to grenade and send shrapnel through the fuel system.
Change your fuel filter regularly and make sure you get good fuel. If your water in fuel light comes on, pull over and drain your separator. Some guys use cheap 2 stroke oil in their fuel to add lubrication. This isn’t proven to help but also haven’t read anything it can hurt. Some guys say it’ll clog the emissions faster, but no proof to back that up that I’ve seen. I would suggest getting a good lift pump for added filtration and separation.
And like James said, search is your friend. I’m just bored and typed all this out lol
Don’t let it scare you. You didn’t buy a ford 6.0 or 6.4. You’re not going to randomly need an entire new engine more than likely. Just make sure you save up a bit of money for when it fails. I’m going to attach a link for Lincoln diesel. They are a vender on the site and have the best prices on fuel systems for duramax. As you’ll see, there are many options for replacement and they’re not very pricey at all. In fact the more basic kits are about the same price for injectors, lines, and pump than most other stock duramax injectors are by themself.
https://lincolndieselspecialties.co...cp4-conversion-catastrophic-failure-kits.html
Change your fuel filter regularly and make sure you get good fuel. If your water in fuel light comes on, pull over and drain your separator. Some guys use cheap 2 stroke oil in their fuel to add lubrication. This isn’t proven to help but also haven’t read anything it can hurt. Some guys say it’ll clog the emissions faster, but no proof to back that up that I’ve seen. I would suggest getting a good lift pump for added filtration and separation.
And like James said, search is your friend. I’m just bored and typed all this out lol
Don’t let it scare you. You didn’t buy a ford 6.0 or 6.4. You’re not going to randomly need an entire new engine more than likely. Just make sure you save up a bit of money for when it fails. I’m going to attach a link for Lincoln diesel. They are a vender on the site and have the best prices on fuel systems for duramax. As you’ll see, there are many options for replacement and they’re not very pricey at all. In fact the more basic kits are about the same price for injectors, lines, and pump than most other stock duramax injectors are by themself.
https://lincolndieselspecialties.co...cp4-conversion-catastrophic-failure-kits.html
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Mine has 106k on the clock and counting. I do however change my fuel filter often and AC Delco only. I have a lift pump, but without additional filtration. What I do use every single tank is Stanadyne fuel additive, so hopefully that keeps it from going boom.
I mean c'mon, 6.0s and 6.4s aren't that bad. They don't have a stellar history but they are not going to magically blow up. A 6.4L suffers the same type of piston failures that LBZ/LMM do but they happen more frequently simply because with an off-road tune they can hit 600whp+ on a fast spooling set of factory compounds which also increases cylinder pressure. LBZ/LMM have been known to suffer similar fates.
I’m neither agreeing more disagreeing with you. A lot of guys love them. A lot hate them. I know of some 6.0 trucks that have failed bone stock. Some go forever. 6.4 same way. But you can’t tell me that you see a more duramax engines needing major work in bone stock form besides crank or lbz piston issues. Stock everything duramax with a built trans can hit 550. And I don’t think I’ve heard of many people blowing a bottom end at that power level and still spools nicely. But the fords have a much greater reputation for failures. That point can not be denied. I still think both of those trucks are some of the best looking ever made and may have one one day, but still, they fail a lot.
I've only personal known of one out of hundreds of trucks and he filled from drop tanks regularly. I still say it's a fuel contamination issues, should it wreck the entire fuel system, No. Just run clean fuel from known stations add some additive and roll with it, I know of several pushing 500k pulling heavy completely stock let alone cp3 swapped. If it does let go just buy new injectors, they are cheap as hell for LML now...
Moved to LML section. Please search in here, you'll find a lot to read.
Keep in mind, every version of the Dmax had their issues.
Keep in mind, every version of the Dmax had their issues.
I have a customer right now who is experiencing the exact some do it some dont deal.
His 2016 3500 with 140k miles grenaded.
His 2011 3500 with 400k miles is original.
Trucks are twins just 5 years apart.
Same maintenance schedule, same delco filters, same routes traveled, same fuel stations used same trailers and loads pulled stock work trucks.
His brothers 2012 3500 just got dropped off the other day too, it has a broken crank. When it rains it pours I guess.
Makes for a good 4th quarter for the shop though!
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His 2016 3500 with 140k miles grenaded.
His 2011 3500 with 400k miles is original.
Trucks are twins just 5 years apart.
Same maintenance schedule, same delco filters, same routes traveled, same fuel stations used same trailers and loads pulled stock work trucks.
His brothers 2012 3500 just got dropped off the other day too, it has a broken crank. When it rains it pours I guess.
Makes for a good 4th quarter for the shop though!
Sent from my SM-G960U using Tapatalk
What do you think of these ideas?
I have used Rev-X Distance in my previous LBZ to provide lubrication for the fuel injectors because of ULSD fuel. I have heard that CP4 problems are partially due to pump cavitation. A lift pump can virtually eliminate cavitation by supplying fuel at pressure and with almost no air in it. Also, I have heard about the Exergy Duramax System Saver fuel pressure regulator that is advertised to prevent CP4 failure shrapnel from destroying the entire fuel system. I think installing these would be somewhat less expensive than a CP4 to CP3 swap. I wonder what some of you think. Thank you.
I have used Rev-X Distance in my previous LBZ to provide lubrication for the fuel injectors because of ULSD fuel. I have heard that CP4 problems are partially due to pump cavitation. A lift pump can virtually eliminate cavitation by supplying fuel at pressure and with almost no air in it. Also, I have heard about the Exergy Duramax System Saver fuel pressure regulator that is advertised to prevent CP4 failure shrapnel from destroying the entire fuel system. I think installing these would be somewhat less expensive than a CP4 to CP3 swap. I wonder what some of you think. Thank you.
There are two major ways the CP4 fails. One, the roller stops rolling and two, the roller/follower twists in the bore. Both cause the roller to slide over the cam causing it to grind up and wear down. This does two things. It reduces the lift of the plunger causing loss of fuel pressure and also sends metal particels into the fuel system
Dirty fuel can jamb up the roller, low lubrication can cause the roller to stick, cavitation can do it too. Or just the right bump or vibration can cause it.
As mentioned above, there is no surefire way to prevent it except for a CP3 swap.
Getting good clean fuel and pressure is not going to harm it, it may make it last longer but you will never know when it will be
TDIclub forums for the VW diesel crowd has pages and pages of discussions on this. Same basic pump but one less piston. The TDI has a lift pump and an axillary pump providing approximately 75 psi to the CP4. The filter is decent too and they still fail.
If you are worried then replace it with a CP3. If not then save up for the CP4/injector kit for when it does
Dirty fuel can jamb up the roller, low lubrication can cause the roller to stick, cavitation can do it too. Or just the right bump or vibration can cause it.
As mentioned above, there is no surefire way to prevent it except for a CP3 swap.
Getting good clean fuel and pressure is not going to harm it, it may make it last longer but you will never know when it will be
TDIclub forums for the VW diesel crowd has pages and pages of discussions on this. Same basic pump but one less piston. The TDI has a lift pump and an axillary pump providing approximately 75 psi to the CP4. The filter is decent too and they still fail.
If you are worried then replace it with a CP3. If not then save up for the CP4/injector kit for when it does