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High Mileage Reports - With Stock Cp4

97K views 171 replies 70 participants last post by  Ogre6988 
#1 ·
I'm looking to hear from who out there has some higher miles and have not had any issues with their Cp4?


I've currently got 32,000 on my '16, but im tossing around the idea of trading it in next year before the new HD comes out, and getting an '18 with the LP5. I'm just trying to decide on if I want to stick with the grenade under the hood or trade up to the LP5. A Cp3 swap isn't out of the question either, but I'm hard pressed to put that kind of money into an already expensive truck just to make it more reliable.

Just looking to see who has taken the gamble and beat the house! :grin2:
 
#3 ·
Just traded my 12' with 102,000 miles for an 18'. It made 460rwhp and 900tqs with a single Kennedy lift pump and never missed a beat, that truck hauled ass. I also ran stanadyne additives year round. I traded it in because I wanted a new truck, otherwise im confident that truck would have made it a long time without any mechanical issues. I did all the mods at 5k miles so it lasted almost 100k basically maxed out. Don't let the CP4 scare you off, if you like your truck just keep rockin it.
 
#9 ·
150k+ 2012. Running fine. Did install a Kennedy single with two filter heads a year ago tho. I also use stanadyne performance formula every tank.
 
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#11 ·
2011 is at about 140,000 so far no problems with the CP4, knock on wood.
 
#12 ·
Thanks for the replies, I'm glad that some CP4's are doing their job and racking up the miles.

I'm still up in the air on what to do with my LML. I think for the time being I will get my Kennedy LP installed and see if the new MPROP from Exergy does it's job if/when someone's CP4 takes a dump. Then come back next summer and either take up a 2019 before the new HD comes out, or ride it out with my LML.
 
#14 ·
I’ve got a 2016 with 48,000 miles and have felt as you thinking about the cp4. So far of all the trucks I’ve owned since 1981 which were ford, dodge, Chevy and gmc all diesels, this 2016 has been the only one not taken back to the dealer for warranty work. I have no dead pedal and this truck does get with the program when you get into it so much so that the 2017 and the 2018 L5P I extensively test drove did NOT impress me at all. In fact I was underwhelmed by the L5P. Maybe mine is exceptional, who knows, but when comparing my current LML to the L5Ps I’ve driven, I would not trade. I also have extended warranty so I am just going to maintain my truck properly and enjoy it.
 
#17 ·
I’m at 49K on my 16 and am in the same boat as audiomixer. I traded in my half ton in March and originally went to look at the 16 that I wound up buying. It was a company lease turn in, 42K on it, not a scratch, speck of dirt, dent, nothing it was as clean as the brand new trucks on the lot. It was actually being looked at by another customer when I got there so my salesman buddy put me in the same truck but an 18 with the L5P. It ran good, not great but good. Then I got in the 16 and it was a whole different animal. Maybe the new one needed to be broken in and would make more power when it loosened up but I was not at all impressed with it when compared to the one I took home.
 
#20 ·
If I had a CP4 I'd keep it and see what it did. Most likely it would be just fine. If I was really worried about the cost of having it let go I'd get an extended warranty that covered it. That would be a lot cheaper than a CP3 conversion.

If I was going to be taking my truck to a place where I could die if it let me down then I'd probably convert it to a CP3 before I left but more likely I'd trade it in and get a 12 valve Cummins in a Dodge. Not that I think the Dodge would be the best truck but the all mechanical Cummins is about as reliable as an anvil. They just keep going.

From this thread we see that the CP4 isn't doomed. It may not be as solid as a CP3 but it isn't worthless either.
 
#25 ·
I bought a completely stock 2011 LML with 134,000 in July of this year. The only thing its had done was a DEF tank replaced under warranty. I'm up to about 140,000 now and just installed an Airdog II 100gph lift pump last weekend. I've also been using the XPD additive since my first tank. I plan to leave it stock unless the emissions start giving me trouble. Hopeful that I can get many more years of service out of this CP4.
 
#27 ·
What tends to fail are the injectors and until GM or Bosch improves the design to extend the life going to a 2018 diesel is not going to provide any magic. Better to put you money into improving on the fuel filtration for the truck. Diesel is a very dirty fuel and even when the GM filter removes 98.7% of the particles that still leaves more than 240,000 particles per gallon burned that are hitting the injectors at high speed.

And filters that are rated at 4 microns will let 10 micron and larger particles through the media. More filtration is the only answer as changing the filter more often actually results in less overall filtration until the filter has been loaded properly (same as with a new air filter that filters less effectively initially).
 
#29 ·
Just turned 131,000 miles. Only problems have been DEF tank heater failure (replaced under warranty), a NOx sensor and a glow plug. Completely stock. I do use a cold weather fuel additive and the engine heater when the OAT drops below zero. No plans to delete as I'm in an emissions inspection state.
 
#34 ·
Well injection pump has gone bad, @ under 600,000 miles on the 2013 srw. 3 times in temps in the low teens, codes p0171, p0087, and p128e appeared followed by a stall condition. First two times i was able to reprime the fuel system drive on my way pulling a camper to Montana where it warmed to the mid 40s. The third time headed back it east, no longer pulling, made it about 1/3 of the way through Wisconson where temps returned to the low teens. Watching on the Edge cts this time the truck began to fluxuate other 10 kpsi on the rail and when I pulled off the interstate exit stall. Change the fuel filter primed and just a fast crank.

Had it towed to a dealer. Tech says he inspected system, then tried to bottle feed bypassing fuel tank, still no start. Luckly he stated no metal flakes or shavings were seen from injection pump....

They say the diesel tech is booked up, might be 2 weeks till it is replaced.
 
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