Most common reason I know of is pump failure resulting on total fuel system replacement and cleaning.

 

Didn't say it wasn't the most common, just that there were other things that need the cab pulled and some of them may not need the cab pulled, just that some tech may choose to do it because they are fast at it and it helps make or beat flat rate. They gotta flag as many hours a shift as they can to keep beer on the table.

 

Cummins' lifter failures...

 

This was my thinking… the dealership’s are also shops. They work on vehicles, so seeing a cab pulled isn’t anything out of the ordinary at a shop. And just because the cab is pulled doesn’t mean it’s a fuel issue… they pull the cab for upper oil pans too… and I’d wager a number of other reasons too. But it’s comments like that which do stir the commotion about CP4’s. Now every time a cab is pulled it’s another CP4 failure, automatically.

And yeah, both Ram and GM had a terrible time with their CP4’s… much worse than Ford. I can’t tell you if they pull the cab for them, but I bet it wouldn’t be uncommon to see cabs pulled in their shops either. It is a shop…

 

Overkill, good links and info.

I remember we were talking about this a while back as well, although not in the sense of "Is this needed?" but more so as a review and why it was chosen. I have 365k on my '14 SD, and am either towing or driving cross country on a regular basis, sometimes doing both. Since I bough the truck well out of warranty (215k), there is no hope in that regard there should something occur. As stated by others, it's the game of Russian Roulette can't be afforded and potentially winding up stranded somewhere on I80, I90, or I15 with no real hope for help should the pump fail. (That said, I'm still on the factory SST, which is just as risky).

I chose to swap to the DCR because even after buying a DPK, if the factory pump fails, you still have to buy a new pump which is near the cost of the DCR. The way I figured, it's better to buy once, cry once and have some piece of mind. I made the swap around 315k, as preventative maintenance and still have my factory pump on the shelf for fun. (Some day for science, I'll take it apart.) For the CP4, I was sure to use fuel from stations with high turnover, but only used additive (Hot Shot's Secret EDT) when I was rolling cross country. I've had the filter gel up a couple times, but no real issues. I keep an extensive log for maintenance, and will point out that I unintentionally "extended" a fuel filter change. My point being, while there is a probability that some of the CP4s (and GT32s) will live, and for a while at that, I don't want to take that risk when I'm working the truck, which is my reason for the change. Finally, I'll add that it's telling when both Ram and Chevy will swap in a CP3 rather than a CP4 when theirs fail...

Now, come this week when my turbo kit arrives, I may not have to grit my teeth every time I'm pulling my trailer up a pass...

 

That's what I do... or least try to... present info that maybe not all will look at or find helpful, but if just one person does, that's what I do it for.

As to your particular truck, I don't blame you for skipping over the DPK and going straight to the DCR with those road trips you take, plus the mileage your CP4 had on it anyway.

What turbo you end up going with?

 

Best reason in thread thus far, to add it only costs a lil' more to go 1st class.

 

Globally, Bosch has made over 60 million CP4s of all varieties. Ford has had them since 2011, GM from 2011-2016 (with no lift pump), Dodge (19-2020, IIRC and their famous recall) VW uses them, BMW uses them, Nissan used in them the abomination that was the Cummins ISV and many more.

Big issue is ASTM D975 allowing US diesel fuel to have a maximum wear scare rating of 520um, while European diesel under EN590 has a limit of 460um. Not a unique issue to CP4s but does play to the weaknesses of the pump.

 

I went with the Stage 2 Predator GXR-64 from Turbo Time USA. This will be a 17-19 conversion. I'll be creating a thread for the swap once all the parts are in, not because the swap is novel in any way, but because there is little info on the company and I want the next guy that's researching options to have a point of reference.

 

I've had 3 6.7 and put a DPK on all three of them. Knowing the CP4 is an achilles heel and that a DPK will prevent damage to the expensive stuff is the key to longevity. Using additives is nothing new to me, been using diesel additives since my first Diesel in 2003, just because. Actually, before that even as I got my Kubota in 2002. that little bugger still runs great after all these years.