I am at 93k on my 2015 LML. I had planned to do a full delete after my warranty is gone but that seems to be a home garage and canada tuner arrangement now. So I think I am going to go the emissions compliant route. My truck is currently bone stock aside from some suspension/wheel changes.
My plan was to safeguard my fuel system with an exergy system saver and a lift pump (cant decide which one). Then throw some duramax tuner tunes at it. And I am at least doing this in the mean time.
But being that my buddy just blew his 16 gmcs cp4 I am thinking of going a little deeper. He was at 75k and baby drives that truck by the way...
Anyways, Im considering going with an S&S CP3 conversion or an exergy 10mm cp4.
The CP3 kind of speaks for itself and this kit is 50 state carb compliant and doesnt require tuning, which I think is nice for selling the truck in the future.
However the guy from duramaxtuner tells me the cp3 isnt without its failures and I have to hack up the fuel system to do the conversion. He assures me the exergy cp4 has upgraded components beyond the system saver metering valve and is a direct drop in. I believe the exergy pump requires tuning to run though which is a negative for when sell the truck as not everyone wants it.
I have also seen guys having fuel line leaks after their cp3 conversions where they did the line install. I certainly dont want that.
Im having some trouble making a decision. What is everyones opinion?
let me start with this. The CP4 issue is blown out of proportion. The total number of failures is very low, they are just concentrated at places like forums so the problem appears larger. Thats not to say its not a problem, it is, but its not the ticking time bomb everyone thinks it is based on this and other forums.
Now that we have that out of the way for context, the CP3 is a significantly superior pump in terms of longevity as well as failure mitigation. The internal design of the CP4 is the issue, so upgrading part quality will help, but ultimately, it doesn't matter how high quality the parts are if the design is deficient. This topics been beat to death on this forum so if you want to know more there are several very lengthy threads to explain the differences in the pumps. Basically the CP3, if it were to fail, wont send metal through the high pressure system, or at least is far less likely to. The CP4 is guaranteed to send metal through the fuel system when it fails.
For this reason i would run the CP3 if you were replacing the pump. Also, ive seen the kits online and its far from "hacking up the fuel system". As for the fuel system saver, there is no evidence one way or the other at this time to show if it makes a difference. Personally, im not convinced they will make a significant difference in the failure.