CP4 Changes - to large dimple symmetrical cam version

[Deleted member 80]

Well, I was hoping to post that Ram/Cummins saw the light, and dumped the dreaded CP4, but that is not the case. There is a running change apparently taking place on the pump internals, from an asymetrical to a symetrical design. The main reason to post this is because the ECM has to be flashed with the correct tune to match the pump on the truck.

 

[MikeXM]

Question is... does it change anything about reliability? I mean they must be a valid reason to do this change.

 

[Brutal_HO]

I'd like to know how to tell the difference.

 

[BighornHDRam]

I wonder how one is to tell the difference on my replacement CP4 pump at 2200 miles of 68503523AA they replaced back in February Symetrical or Asymetrical that proceeded to blow the fuel inlet line off after 6 miles, as I don't remember them doing a ECM reprogramming after but it still has a weird rattle from the CP4 pump that I can duplicate just by turning on the fast idle that starts at 1100 rpm's that goes up from there and you can hear it as you drive down the road.

I wish Ram would get past the discovery phase that's been going since March on my lemon case so I can be done with this truck but Ram is using this Covid to drag out all buybacks and swaps since the courts are letting them.

 

[carlrx7]

I'd like to know how to tell the difference.

View attachment 6349

4:50, 4 dimples = old design

 

[Deleted member 80]

They went to a less aggressive ramp angle on the cam/rotor in the pump. This will probably make them last long enough to get out of warranty

 

[mostcorey95]

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[Rich]

Well, I was hoping to post that Ram/Cummins saw the light, and dumped the dreaded CP4, but that is not the case. There is a running change apparently taking place on the pump internals, from an asymetrical to a symetrical design. The main reason to post this is because the ECM has to be flashed with the correct tune to match the pump on the truck.

View attachment 6347

Where did you get your service bulletin from. I know its not the same but I ran my vin and there is no recalls or campaigns.

 

[mostcorey95]

Where did you get your service bulletin from. I know its not the same but I ran my vin and there is no recalls or campaigns.

There are no open recalls for the cp4 only service bulletins. To alert techs of the new design.


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[Rich]

4:50, 4 dimples = old design

So I just watched the video. The guy is a little scattered brain but he gives good information. Has anybody else checked there fuel pump dimples. I have neither 4 or 1 dimple configuration, I have a 2 dimple pattern. I'm not sure what that means. More than likely, different numbers and patterns and locations mean different things. Lots of possibilities, I can see this simple thing taking off trying to figure out what they mean for model differences. It does sound like the 1 dimple is the latest and greatest technological advancement on a crappy pump, wich means mine is not the best with a build date of January 20. I did like what he said about the hot shot additive, I'll have to check that stuff out.

 

[mostcorey95]

So I just watched the video. The guy is a little scattered brain but he gives good information. Has anybody else checked there fuel pump dimples. I have neither 4 or 1 dimple configuration, I have a 2 dimple pattern. I'm not sure what that means. More than likely, different numbers and patterns and locations mean different things. Lots of possibilities, I can see this simple thing taking off trying to figure out what they mean for model differences. It does sound like the 1 dimple is the latest and greatest technological advancement on a crappy pump, wich means mine is not the best with a build date of January 20. I did like what he said about the hot shot additive, I'll have to check that stuff out. View attachment 6950

All that low dimples allow fca to do is track what line it was produced on and what batch it was. The single dimple up high is the new version of the pump. I use optilube xdp.


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[Brutal_HO]

All that low dimples allow fca to do is track what line it was produced on and what batch it was. The single dimple up high is the new version of the pump. I use optilube xdp.


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4 low dimples in a square pattern on my Feb 2020 build. I also use Optilube xpd.

In fact, that reminds me I need to order another jug.

 

[mostcorey95]

4 low dimples in a square pattern on my Feb 2020 build. I also use Optilube xpd.

In fact, that reminds me I need to order another jug.

I have seen better results with xdp over edt. That would be the old style pump. Below is the new style. With the single dimple marking and other dimples below. The designation is the single larger dimple in the circled location. That is the only way to tell is if that single dimple is there the other dimples don’t really mean anything besides what line and what batch. So if you don’t have that single dimple which is in every truck after 9/1/2020

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[Rich]

I didn’t select the image apparently it was just going to repost. Yeah I’ve had them tested at minimum dose and max dose and xdp came back better. I’ll find the results they are in my email somewhere.


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So in other words, more than a single dimple and your fubar

 

[Brutal_HO]

So in other words, more than a single dimple and your fubar

Reread the post, I'll paraphrase:

A single LARGE dimple on top is the new symmetrical cam design.

All small dimples low are just for batch control.


RIF

 

[Brutal_HO]

Just so the crybullies don't get in a twist, the OT discussion of additives have been moved to a new thread.

CP4 Changes - additives discussion

I have seen better results with xdp over edt. That would be the old style pump. Below is the new style. With the single dimple marking and other dimples below. The designation is the single larger dimple in the circled location. That is the only way to tell is if that single dimple is there the...

hdrams.com

 

[John Jensen]

I thought I understood this dimple data until I looked at my CP4.
My 2020 3500 HO was built 3/16/2020 and has 7 small dimples - what the heck does that mean?

 

[mostcorey95]

I thought I understood this dimple data until I looked at my CP4.
My 2020 3500 HO was built 3/16/2020 and has 7 small dimples - what the heck does that mean?

That’s just to tell what line and what batch it is from. If you look above and have the large single dimple under the supply line that goes to the rail that is circled in red. The one large single dimple with other dimples down lower that is the new style pump.


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[John Jensen]

That’s just to tell what line and what batch it is from. If you look above and have the large single dimple under the supply line that goes to the rail that is circled in red. The one large single dimple with other dimples down lower that is the new style pump.


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I don't have the large dimple that you mention. And I misspoke, 8 small ones, not 7.

 

[Rich]

I thought I understood this dimple data until I looked at my CP4.
My 2020 3500 HO was built 3/16/2020 and has 7 small dimples - what the heck does that mean?

I've got the 2 dimple with a January 20 build date. Like the guys say, it's probably just batch differences, hopefully not actual product differences in each batch, that would make for a lot of different scenarios of product description