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

[Millmutt]

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.

I think Ram may be the only entity that knows the true failure rate and it may not be nearly as high as the temperature on these forums.
The real bummer is the down time awaiting parts. Sounds like the actual repair may be only a couple of days but the supply chain timeline is weeks or months.

 

[leeroy300]

I think Ram may be the only entity that knows the true failure rate and it may not be nearly as high as the temperature on these forums.
The real bummer is the down time awaiting parts. Sounds like the actual repair may be only a couple of days but the supply chain timeline is weeks or months.

the sad part is that when you buy a high end truck you expect it to be as good as or better then the previous years model. FCA should have seen from the competitions issues with the CP-4 and not switched. I bought my 2020 because of the reliability of my 2014 and that is a huge reason I did not go to Ford and now to have to worry about a known issue that Ford has been having is sad.

 

[Millmutt]

I would suspect that Ram is well informed about all the pumps. I can’t fret over a failure that may never occur, if I did I would never get off the couch. I just going to enjoy my 2020

 

[Deleted member 80]

I think Ram may be the only entity that knows the true failure rate and it may not be nearly as high as the temperature on these forums.
The real bummer is the down time awaiting parts. Sounds like the actual repair may be only a couple of days but the supply chain timeline is weeks or months.

Listen to the current diesel podcast with S&S Diesel as the guest. The guy was an engineer at Cummins for years. He said when they heard the CGI Cummins was going to the CP4 they rushed out to locate an engine to immediately begin work on a CP3 conversion. There is no speculation in knowing the CP4 is garbage.

 

[Xflight29]

Listen to the current diesel podcast with S&S Diesel as the guest. The guy was an engineer at Cummins for years. He said when they heard the CGI Cummins was going to the CP4 they rushed out to locate an engine to immediately begin work on a CP3 conversion. There is no speculation in knowing the CP4 is garbage.

I just can't figure if Ford, Chevy and now Ram trucks for past 10 years have knowen that the pump is crap and exspensive for them to warenty not to mention truck reputation, just amazing Ram picked this pump.

 

[Epsilon Plus]

Oh yeah, totally, the failure rate is probably not that bad. That 'ol trope. FCA totally just revised a pump a year and a half into production, and then completely abandoned the new revision and overall design a few months later.

Total coincidence. Happens all the time. They love spending useless money for 0HP/0TQ/0MPG gains like that.

Failure rate is not that bad.

 

[mra400ex]

the sad part is that when you buy a high end truck you expect it to be as good as or better then the previous years model. FCA should have seen from the competitions issues with the CP-4 and not switched. I bought my 2020 because of the reliability of my 2014 and that is a huge reason I did not go to Ford and now to have to worry about a known issue that Ford has been having is sad.

Agree...May never happen but each year should be an improvement, not a possible grenade. Aftermarket came out with a solution to keep CP4 particles out of the fuel system. Even to come up with something like that would be an improvement. But FCA has definately removed doubt there are lots of failures by going back with the CP3.

 

[H3LZSN1P3R]

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.

My theory is the bores the lifters ride in are over size slightly allowing the lifters to turn on some pumps not all of them

 

[Brutal_HO]

Posted on another forum:

Sure looks like the rumored CP-ISB21 pump. As I understand it, been in the works for a while.

About time someone actually took a pic of the dang tag.

 

[NordicNevs]

Posted on another forum:

Sure looks like the rumored CP-ISB21 pump. As I understand it, been in the works for a while.

About time someone actually took a pic of the dang tag.

View attachment 12250

Haven’t heard of this pump. Can you elaborate?


Sent from my iPhone using Tapatalk

 

[Brutal_HO]

Haven’t heard of this pump. Can you elaborate?


Sent from my iPhone using Tapatalk

I don't recall where I saw it, but someone (possibly here in this thread) was talking about the CP-ISB21 pump in development.

It's clear it's not an actual CP3, but rather this new pump based off the CP3.

When I find that post, I'll be sure to link it and give credit.

 

[Brutal_HO]

Found it: This guy called it. Forgot about the second post with the pic. A few people gave him a lot of crap about being wrong too...

I even commented, "Translation says, "19-20 CP4 owners will get CP ISB21 retrofit!"

I am glad i have a 2016! and a cp3

www.cumminsforum.com

I am glad i have a 2016! and a cp3

www.cumminsforum.com

"My brother emailed me this page from local newspaper few weeks ago. He works for Bosch in Czech Republic where they are making CP3, CP4, and CP5 diesel pumps. After Christmas break, starting build new pump CP ISB21 for Cummins."

 

[NordicNevs]

Interesting. Let’s hope it’s reliable lol. I’d consider a swap even with the conversion I have already done to be honest depending on cost


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[Brutal_HO]

@RamCares

Any word on this "service action" we're all anxiously awaiting? Sure would be stand up of RAM/FCA/Cummins to retro this CP-ISB21 pump into our trucks before they grenade.

Please PM me the TSB before publishing it so I can be first in line.

 

[camojimmy]

Hopefully more news comes out soon.

 

[Cummins3]

Doubt it

 

[mra400ex]

I guess semi retired mechanics like myself are just "mental"... Anything we drive or have had experience with we think about the stuff that can go wrong. I believe this CP4 problem is real or RAM /FCA/Cummins would not have gone back to the CP3 pump. I test drove a 2021 F250 with the 7.3L Gas and 10 speed trans. Of course it is not as strong as the 6.7L HO, or the 6.7L standard. But it had 2 miles on it so I did not hammer on it, but you could tell it had good torque. The 10 speed transmission is SWEET. Very flawless in shifting and smooth. I have 2 dealers figuring a trade and will see where that goes. One is for a F250 with the Tremor package which is pretty cool. Ford definitely has the better mirror setup and they extend electronically. Biggest aggravation with the CP4 to me is their lack of parts availability when you have a failure and the amount of time your vehicle is down. Will see how bad the dealers are on trade $$$$. I will probably be in the 8 to 10 K miles per year and probably should have went with the new 7.3L gas. I planned on keeping the Ram Cummins and being the last truck I own, but down the road long term out of warranty is scary when all these problems pop up being brand new.

 

[Brutal_HO]

I guess semi retired mechanics like myself are just "mental"... Anything we drive or have had experience with we think about the stuff that can go wrong. I believe this CP4 problem is real or RAM /FCA/Cummins would not have gone back to the CP3 pump. I test drove a 2021 F250 with the 7.3L Gas and 10 speed trans. Of course it is not as strong as the 6.7L HO, or the 6.7L standard. But it had 2 miles on it so I did not hammer on it, but you could tell it had good torque. The 10 speed transmission is SWEET. Very flawless in shifting and smooth. I have 2 dealers figuring a trade and will see where that goes. One is for a F250 with the Tremor package which is pretty cool. Ford definitely has the better mirror setup and they extend electronically. Biggest aggravation with the CP4 to me is their lack of parts availability when you have a failure and the amount of time your vehicle is down. Will see how bad the dealers are on trade $$$$. I will probably be in the 8 to 10 K miles per year and probably should have went with the new 7.3L gas. I planned on keeping the Ram Cummins and being the last truck I own, but down the road long term out of warranty is scary when all these problems pop up being brand new.

The CP4 was just a stop gap filler to meet emissions until the CP-ISB21 pump was ready.

IOW, RAM/FCA/Cummins didn't "go back" to the CP3, they went forward with the CP-ISB21.

 

[Epsilon Plus]

Thrilled to have paid $70k for a stop gap.

I suppose at least there will be glitter at the party...

 

[Carpenterhow]

Thrilled to have paid $70k for a stop gap.

I suppose at least there will be glitter at the party...

All that glitters is not gold.