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CP4 to CP-ISB21S3 (revised CP3) change for 2021 6.7L Diesel Trucks -- Merged Threads

GBB

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That's the first I heard a difference, thanks! I have been wondering why the Ford forum is incredibly focused on death wobble and they barely seem to care about the cp4 compared to this forum. If they're both using identical pumps I couldn't understand why such a difference in reaction, especially after 8ish years on the powerstroke
Ford is only one with class action suit on the CP4...covering models from 2011. So they’re definitely having problems.
 

Xflight29

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I didn't design the pump so I can't speak to any of that. I only know that the RAM CP4 is 50% overdriven vs the Ford/GM pump and it's a smaller size pump (6mm vs 8mm I believe). I do know that the higher RPM of the RAM pump is likely the key cause of it's failure. High RPM equals a lot of heat, then you take the fact that numerous items could make it so the pump has air/water in it and it's game over.
How are you getting your data . Ford owners are saying they have as much of a frailer with their pumps as Ram and GMC .
 
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UglyViking

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How are you getting your data . Ford owners are saying they have as much of a frailer with their pumps as Ram and GMC has.
Purely observational based off lurking forums and fb groups when I was deciding between Ford/RAM. It's not hard data by any means but my observation is that the discussion is brought up much less often than similar RAM groups. Take that for what it is, a personal observation, nothing more.

As far as the difference between pumps and overdriven, you can easily find that across multiple sources but I first heard of it through firepunk so credit to them.
 

GBB

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How are you getting your data . Ford owners are saying they have as much of a frailer with their pumps as Ram and GMC has.
Heard Chevy/GMC swapped over to a Denso pump...don’t know how that is working out for them
 

LossPrev

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Ford is only one with class action suit on the CP4...covering models from 2011. So they’re definitely having problems.
Not saying they aren't having problems and I know Ford and GM both had lawsuits over the cp4. Like Ugly Viking said, purely anecdotally the Ford forum, Facebook groups and youtube just don't talk about it much compared to the Ram cp4 issues. I joined many Ford groups when shopping for a truck a year ago and still follow them from time to time.

I know thats not very scientific but it is enough for me to notice for sure. There could be many factors causing this as well, we don't have a death wobble problem so the cp4 gets more attention? Idk
 

Xflight29

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Not saying they aren't having problems and I know Ford and GM both had lawsuits over the cp4. Like Ugly Viking said, purely anecdotally the Ford forum, Facebook groups and youtube just don't talk about it much compared to the Ram cp4 issues. I joined many Ford groups when shopping for a truck a year ago and still follow them from time to time.

I know thats not very scientific but it is enough for me to notice for sure. There could be many factors causing this as well, we don't have a death wobble problem so the cp4 gets more attention? Idk
I think it is that Ram owners are just smarter than Ford owners and like to discuss issues hoping Ram Care is listening to make much needed changes.
 

Pronto

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That's the first I heard a difference, thanks! I have been wondering why the Ford forum is incredibly focused on death wobble and they barely seem to care about the cp4 compared to this forum. If they're both using identical pumps I couldn't understand why such a difference in reaction, especially after 8ish years on the powerstroke
That would make sense that there's a difference in the pumps. Crazy how Ford can't get the death wobble tamed through multiple generations of the Super Duty. I know it can happen with any with any SFA vehicle but it happens a lot to those Fords. I had an F250 that did it and it gets your attention, especially the first time it happens.
 

exiledinaz

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That is correct I should have stated that in my response. I meant before they switched.
That would leave Ford hanging as the other 2 big ones switched out....More fodder in the class action lawsuit proving Ford is burying their heads in the sand ignoring the obvious.
 

UglyViking

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That would leave Ford hanging as the other 2 big ones switched out....More fodder in the class action lawsuit proving Ford is burying their heads in the sand ignoring the obvious.
Eh, not quite that simple. Ford can easily argue that their engine and fuel rail design allows/requires they run the CP4 due to bla bla bla. What GM/RAM do on their trucks has 0 bearing on what Ford does with it's truck. GM changed fuel rail/pump suppliers with their change to the L5P engine, so again that is a relatively easy position to defend as they can argue they changed fuel pump due to a new supplier and a new engine design.

RAM on the other hand doesn't have either argue. If they would have stuck with the CP4 they could have at least made the argument that they did not feel the failure rate of the pump rose to the level of a recall and they were making updates to further improve. With them reverting back to the CP3 while on the same engine, after only 2 model years is where it gets them.

So to close, while I don't doubt the Ford CP4 has failures it doesn't seem to be near the same rate from casual observation. Given that Ford sells a lot more trucks I'd expect to see more posts about the topic but I see fewer. There could be many reasons for this including that RAM guys are working their trucks harder, they are more inclined to pay attention to the engine, etc. and until FCA and Ford release failure numbers (won't happen without a court order) we will never know. I do know that just because other manufactures switched away from that pump doesn't really hurt Ford though.
 

mra400ex

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First off I want to say thanks to everyone and all the info we share about the Ram CP4 failures. I talked to a couple independent diesel shops in my area. Both have seen and worked on CP4 failures on all the brands. There is a bypass kit available for the Ford now which reroutes the fuel from the bottom of the CP4 and sends it back to the tank to be filtered again. I also wonder if the Ford tank module is less prone to sucking air when the fuel gets low. Anyway, the shops say if you have the Ford to get the bypass kit ASAP. On the Ram I questioned about the CP4. Like I told the guy, "I went with the Ram because the Cummins was a really good motor for us at UPS." He said pre 2019 he would agree. He thoughts were that as soon as your warranty is done, convert to CP3. This was several months ago when we talked...... Now it appears that chances are high you will have failure in warranty and be without your truck for quite a while as it appears parts, etc. are a problem. Look at what we are having to do. 1) Worry about your fuel quality. 2) Be sure to add a fuel additive. 3) Don't go below 1/2 a tank (which is a pain if working the truck) 4) Wonder when and where the CP4 will lay down on you. Overall this is a very sad situation for every brand. Aeration can be cured with the Fass system. Apparently it prevents aeration of fuel and also part of the install is modifying the fuel pickup in the fuel module. But why should we be pouring the $$$$ into these things to prevent a problem on a new vehicle. I love the strength of the 3500 and the 6.7HO and Aisin trans, but getting tired of the wait for a solution from RAM and Cummins. It is sad when you were excited about your new truck and now the name for your new truck is the "DAMN DODGE". I feel like I should have waited for the 7.3L gas motor from Ford.
 

boatdude1

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When was this released? Also do you have the tsb number. I’m going to need this done as well. For a 70k truck they are sure stacking up.
The A/C fix is #24-001-20. Made a big difference on my truck.
 

bigcitymike

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I search the tfltruck.com site and didn't see any reporting on the CP4 issue as it relates to Ram. It's a good opportunity for them to do an investigative report on the matter to generate some traffic.

I wonder if this could be related to fuel contamination? Delivery truck started dumping gas in the diesel tank, recogonized the error and just swapped it w/o telling anyone? Or maybe the bio-diesel that seems to be everywhere has a higher percentage of bio mix than it should. These issues would be random, and impact the customer exposed would result differently, as not all injectors are as frail as the CP4.
 

Xflight29

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What I can't wrap my brain around is seeing it's a design issue in which I agree with is , why some fail and some don't.
A design is a design built the same over and over.
I know of A lot 19 and 20 that have well over 150000 miles with not one issue.
 
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Not surprising that some units of poor design survive by pure random dumb luck. Some 6.0 Fords ran a while. When I was in the OPE business Kohler came out with the KT17, which was a notorious grenade, but they didn't all come apart. Lots of other examples exist.
 

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