The CP4 Disaster: Disaster Prevention Kit or full DPK?

[DieselNerd]

My 2015 6.7L is still running the original CP4. I'm terrified of it "grenading" and sending metal shards through my entire fuel system. Is the "Disaster Prevention Kit" enough to save my injectors, or should I just budget for a CP3 conversion?

 

[CrankshaftCal]

I totally get the anxiety. I installed a DPK on my '16 last year. Here’s the deal: the DPK doesn't stop the CP4 from failing, but it reroutes the fuel flow so that when the pump inevitably 'grenades,' the metal debris is sent back to the tank and through the return filters instead of being forced into your injectors and fuel rails. A $400 kit can save you from a $10,000 repair bill. If you aren't planning on pushing huge horsepower and just want to protect your investment, the DPK is the most cost-effective insurance you can buy.

 

[IronChassis]

I’ve seen too many guys say 'I'll just wait and see' only to end up with a $12,000 repair bill. The DPK (Disaster Prevention Kit) is a no-brainer. It doesn't fix the pump's design flaw, but it acts as a firewall. If the pump fails, you’re looking at a $1,000 pump replacement instead of a total fuel system overhaul including all 8 injectors, rails, and lines. For a few hundred bucks and an afternoon in the garage, why would you even risk it?

 

[IronWrench]

While we discuss DPK vs. CP3, don't overlook your fuel filters. The CP4 hates air and it hates water even more. I run a DPK, but I also change my fuel filters every 10k miles religiously and always drain the water separator. If you see even a speck of metal in your primary filter housing during a change, stop driving immediately. That’s your early warning sign that the CP4 is starting to eat itself.