Another CP4 option from RCD
Cross-Country
Joined: Nov 2010
Posts: 61
Likes: 39
He brings up some interesting points. Whether they are valid or just good marketing, it definitely made me think about it. If he fixes the rotating lifters in the CP4, what other issues are there? That's really all you hear about, and to his point, could be induced by another problem. I monitor Low Side pressure and never see it dip below 85psi, usually hangs out at 87.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
Lead Driver
Joined: Feb 2005
Posts: 7,970
Likes: 2,665
From: The Great State of Texas
Thanks for sharing and I really like this fix so far but, would like to know what validation was done to ensure long term reliability. Also, I never bought into the catastrophic CP4 failures due to a lack of lubricity of our diesel fuel theory.
Lead Driver
Joined: Feb 2005
Posts: 7,970
Likes: 2,665
From: The Great State of Texas
He brings up some interesting points. Whether they are valid or just good marketing, it definitely made me think about it. If he fixes the rotating lifters in the CP4, what other issues are there? That's really all you hear about, and to his point, could be induced by another problem. I monitor Low Side pressure and never see it dip below 85psi, usually hangs out at 87.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
Cross-Country
Joined: Nov 2010
Posts: 61
Likes: 39
Agreed. Alot of Cummins people at least around me say the 6.7 PS is "junk" because of the CP4 and that's just not the case. I'll keep my "junk" 6.7 PS over my old literal JUNK 6.7 Cummins. Sorry for the derail. I'm excited to see some of this stuff gaining traction.
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Lead Driver
Joined: Sep 2006
Posts: 5,665
Likes: 164
From: Cartersville, Ga
He brings up some interesting points. Whether they are valid or just good marketing, it definitely made me think about it. If he fixes the rotating lifters in the CP4, what other issues are there? That's really all you hear about, and to his point, could be induced by another problem. I monitor Low Side pressure and never see it dip below 85psi, usually hangs out at 87.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
I'm glad to see some effort put into the CP4, I don't think it's as bad as people make it seem. Especially Cummins guys. I know of several high mile 6.7's around me with original pumps. Highest one being just shy of 300k.
I’’m also the guy that has never bought into the “sky is falling” mentality of the CP4 Ford issues. Between the 3 I’ve owned and the 6 I maintain for my brother, only 1 truck had a complete fuel system failure. It was due to contaminated fuel. The 2 pumps I replaced were on 250k+ mile trucks that threw p0087 codes. Trucks ran fine, just HPFP was getting tired.
Laughing Gas
Joined: Mar 2008
Posts: 1,031
Likes: 510
As far as what I've read the greatest majority of CP4 pump failures are from the lifter rotating 90 degrees to the cam, whether that is from bad fuel, or lubricity, or both or neither, doesn't matter.
It would seem that if Bosch would just pin the lifters on the CP4, it would fix 99.99999999% of the failures.
It would seem that if Bosch would just pin the lifters on the CP4, it would fix 99.99999999% of the failures.
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FTE Legend
Joined: Mar 2017
Posts: 31,952
Likes: 9,193
From: Western NY
I don't fall into the "sky is falling" camp either but since my truck is long term truck (now paid off), since a "disaster" can potentially happen, just like an accident on the road, I'd rather have the kit as insurance just like my State Farm insurance.
I keep an eye on my DFCM pressure on my iDash and it probably drops no more than 5 PSI or so from the average pressure while driving by the end of the 3rd oil change which is by the recommended interval of 22.5k miles for my gen truck because I let my truck tell me when to change oil.
As to examining 500k mile pumps with zero wear, is that with the use of straight fuel, a bio blend fuel, and/or use with an additive? Lots of variables that can be involved and need to be addressed before putting out a blanket statement like that. Not doubting his experience on this, but we do know pumps have failed or else there wouldn't be aftermarket solutions like this one addressing the issue.
I have to give it to this guy and this ingenious solution. Hell, I hope to never have to replace my CP4 but we shall see what happens. Great post. Thanks for sharing.
I keep an eye on my DFCM pressure on my iDash and it probably drops no more than 5 PSI or so from the average pressure while driving by the end of the 3rd oil change which is by the recommended interval of 22.5k miles for my gen truck because I let my truck tell me when to change oil.
As to examining 500k mile pumps with zero wear, is that with the use of straight fuel, a bio blend fuel, and/or use with an additive? Lots of variables that can be involved and need to be addressed before putting out a blanket statement like that. Not doubting his experience on this, but we do know pumps have failed or else there wouldn't be aftermarket solutions like this one addressing the issue.
I have to give it to this guy and this ingenious solution. Hell, I hope to never have to replace my CP4 but we shall see what happens. Great post. Thanks for sharing.
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Cargo Master
Joined: Jul 2011
Posts: 2,676
Likes: 979
From: Walpole, MA
Right up there with GM's roll out of the CP4, no dedicated lift pump wasn't the best idea in the grand scheme.
Cargo Master
Joined: Feb 2020
Posts: 2,277
Likes: 949
I thought the S&S guy said in a recent video that the buckets are pinned in the 20+ CP4's. A pump could still fail due to bad fuel or DEF contamination, so a DPK is needed to prevent damaging the entire fuel system.
Fleet Mechanic
Joined: Oct 2022
Posts: 1,823
Likes: 898
From: Dallas Metroplex
Yeah, Overkill mentioned that as well, and I watched the video myself to confirm that's what was said. Definitely gives me a little more solace to know that, as I had no idea that they did so for the 20+ MY's. But, yeah, I still have my SDK to install (once I get some time now that the weather is getting more conducive to working outside).
FTE Legend
Joined: Mar 2017
Posts: 31,952
Likes: 9,193
From: Western NY
RCD added more machining and parts to the pump which would offset the cheap manufacturing of the CP4 pump. I'm sure none of this was even thought of because going from the ivory tower perfect world of engineering to the results of the real world where stuff happens, is two completely different things.
I'll give it to RCD though for this... But the fact remains that the aggressive nature of the cam in this pump plus the imperfect world of modern day ULSD fuel, this won't make the CP4 last longer, but it will prevent contamination of the entire fuel system due to a pump failure.
I'm curious to see how the results of the real world testing with the S&S DCR pump does and if it will offer more reliability and life when compared to the CP4. Time will tell...
Good stuff and conversation going here...
Lead Driver
Joined: Feb 2005
Posts: 7,970
Likes: 2,665
From: The Great State of Texas
I thought Bosch didn't add a feature to prevent buckets from rotating due to some patent, but can't confirm the accuracy of this. Also this new modified pump changes the routing of the fuel in the cam lobe/plunger housing so it doesn't go to the injectors.
Super Moderator
Joined: Jul 2004
Posts: 21,113
Likes: 3,939
From: Ohio
I got hit up the other day by a neighbor who hauls Hay down South and he is a die hard Duramax guy. Their new truck is sitting in the shop with a CP4 pump failure, will have to pass this information on. Nothing for them to rack up 50,000 miles in a short time, he will haul anything. If I need fence posts he will back haul them cheaper from Amish country than what I can buy here. Nice to know people...
FTE Legend
Joined: Mar 2017
Posts: 31,952
Likes: 9,193
From: Western NY
I got hit up the other day by a neighbor who hauls Hay down South and he is a die hard Duramax guy. Their new truck is sitting in the shop with a CP4 pump failure, will have to pass this information on. Nothing for them to rack up 50,000 miles in a short time, he will haul anything. If I need fence posts he will back haul them cheaper from Amish country than what I can buy here. Nice to know people...
I can't remember exactly, because I'm a Ford guy, but
Okay just looked online and the 11 to 16 trucks did NOT have a factory primary pump which was a problem for those trucks.
Ford's still have failures but probably not as many, i would think, as GM because Ford uses a low pressure pump to supply the CP4.
How many miles on his truck John? Or did he buy a Ford?