Cp4 GMC Duramax conversion to cp3 common rail high pressure fuel pumps or similar.

[jjeff]

Yes gm upped that service to 150k miles I think. There's is something to it involving the oil pump I believe also buddy who owns the 3.0 says they can change it by pulling the transmission instead, even so if I own something for150k miles since new I don't mind doing or hiring someone to do pretty extensive maintenance to it if it's not what I consider a problem riddled lemon.

 

[Hay Dude]

So Initial estimate for a cp3 conversion done by what seems like a competent knowledgeable shop Specializing in Duramax engines iand Allison transmissions is 6k includes a 4 yr unlimited mileage warranty. On new cp3 pump and all related components so I guess I'll put my dumper dog box on Temporary hold . Before I spend a fortune to me on this anyone go thru with this conversion what were the results? Power, fuel mileage etc.more important reliability. I definitely don't have a big a problem spending cash hiring others to do things for me I have limited or no knowledge of as long as it's done right and how id attempt to do it correctly. Could buy quite a few winter beaters that I'm comfortable working on for this upgrade. In retrospect even a new 1 ton Duramax with limited functional options retails without incentives for close to 70k. Plus I'd be very leary and not enjoy using it like a pickup truck at that price.

Mine was done under a Ram national campaign. Final cost was like 8k, but $0 for me.
I think the truck might have lost just a tiny bit of power. The CP-4 is a higher performance pump than a CP-3, but it’s not reliable, maybe that’s why.


I’m assuming you are stuck with a CP-4 out of warranty?

 

[jjeff]

Mine was done under a Ram national campaign. Final cost was like 8k, but $0 for me.
I think the truck might have lost just a tiny bit of power. The CP-4 is a higher performance pump than a CP-3, but it’s not reliable, maybe that’s why.


I’m assuming you are stuck with a CP-4 out of warranty?

Correct it's a 2016:with about 125k on it I'm keeping that truck might as well have it done now or pay 2x more later. The cp3 conversion is definitely expensive. However it sure seems like this shop that only specializes in Duramax engines and allison transmissions know what there doing and have been in business since the lb7 generation. So 20+ yrs. They also took the time to give me a pretty thorough overview of what they'd be doing and what may be found including possible further procedures to mitigate any issues found.

 

[Racer4]

Our 2010 VW Touareg has a cp4 pump. 237,000 mi so far. I do give it a shot of power service every couple tanks. Fingers crossed.

 

[jjeff]

Isn't the 3.0 Duramax the one with timing belt that requires the engine to be pulled?

It's actually the oil pump belt that should be replaced at 150-200k miles why they use a internal belt to run the oil pump is beyond me. I think it uses a timing chain also. And early versions had timing chain not belt problems from what I heard from my friend who owned one.

 

[jjeff]

Our 2010 VW Touareg has a cp4 pump. 237,000 mi so far. I do give it a shot of power service every couple tanks. Fingers crossed.

Ive used a fuel lubricity additives fairly often changed fuel filters pretty frequently and rarely ran the ,fuel tank below a 1/4 needless to say im pretty confident it's not going destroy itself for awhile I hope. However it will probably be a $12k job if it does.

 

[ruffdog]

 

[jjeff]

Definitely not a shady tree weekend project for me anyway.

 

[Hay Dude]

Definitely not a shady tree weekend project for me anyway.

I’d skip that video just based on the looks of that guy. lol

 

[Hay Dude]

Correct it's a 2016:with about 125k on it I'm keeping that truck might as well have it done now or pay 2x more later. The cp3 conversion is definitely expensive. However it sure seems like this shop that only specializes in Duramax engines and allison transmissions know what there doing and have been in business since the lb7 generation. So 20+ yrs. They also took the time to give me a pretty thorough overview of what they'd be doing and what may be found including possible further procedures to mitigate any issues found.

I guess if the juice is worth the squeeze.
6K into a truck worth??? What were you asking?

And you were going to sell it to me with a CP-4????
Shame on you.
We’re not buddies anymore.