2015 Duramax fuel pump

[A Don]

I have a 2015 Chev Duramax with 145000 miles on it. It is running perfect and I would like to keep it that way. I am becoming more alarmed by the horror stories of the fuel pump blowing up. Has anyone here replaced one with lots of miles on just as a preventive measure? I wonder what the cost would be?

thanks
Don

[Gavenger]

For the cost of preventative maintenance, it may be more cost-effective to convert from the CP4 pump to the CP3 pump. Or, for a lot less money, and to greatly reduce your paranoia (but not eliminate it completely) you could have a FASS lift pump installed.

[Ray,IN]

I've never heard of a Duramax injector pump "blowing up". I used to have an 02 Duramax dually. It ran fine on biodiesel after the copper gaskets were replaced in the high-pressure rail under the valve covers.(unique problem for early Duramax engine)
As to additive lubricants, this ISO study of different products should be helpful: https://www.dieselplace.com/forum/76...y-results.html
Note, biodiesel additive performed the best - anything below #13 performed worse than NO additive whatsoever.

[tuffr2]

I feel your pain of thinking you are driving a ticking time bomb. I felt the same way driving 6.5 year old gen 1 6.7 powerstroke. I thought the emission system would clog up but it didn't, at least not while I owned it.

Also gen 1 powerstroke had a turbo that would crap out...but mine did not.

Sometimes you got to use the diesel to keep it running. Seems you are doing that.

My thoughts are there are a dozen things that could break. The EGR or the Particulate filter could clog. A high pressure injector could break off and damage a cylinder. You could get water in the fuel and mess up the injectors.

If I say 'If it ain't broke don't fix it' or if I say change it to prevent a future semi-known problem and the tech screws something else up...ugh.

This is something you can flip a coin on imho.

[Gavenger]

Originally Posted by tuffr2

I feel your pain of thinking you are driving a ticking time bomb. I felt the same way driving 6.5 year old gen 1 6.7 powerstroke. I thought the emission system would clog up but it didn't, at least not while I owned it.

Also gen 1 powerstroke had a turbo that would crap out...but mine did not.

Sometimes you got to use the diesel to keep it running. Seems you are doing that.

My thoughts are there are a dozen things that could break. The EGR or the Particulate filter could clog. A high pressure injector could break off and damage a cylinder. You could get water in the fuel and mess up the injectors.

If I say 'If it ain't broke don't fix it' or if I say change it to prevent a future semi-known problem and the tech screws something else up...ugh.

This is something you can flip a coin on imho.

Both the Ford 6.7 and the Duramax LML use the same Bosch CP4 Fuel Pump. However, Ford realized the flaw in the design and installed lift pumps in the fuel tank from the factory. GM did not. The CP4 fuel pump is located near the engine and sucks fuel from the tank.

The issue is, the CP4 is a Euro spec fuel pump and is designed with the additional lubricity of the Euro diesel. So if for some reason an air bubble gets in the fuel line its not that bad, but with our ULS Diesel, lubricity is critical and CP4 will eat itself if you get an air bubble and will throw microscopic metal shards down the high pressure side, towards the engine. And the fix is a complete replacement of the fuel system. Installing a lift pump in the tank will maintain fuel pressure between tank and the CP4, greatly reducing the chance of an air pocket.

[Kraken]

My Fass system just arrived yesterday. I also opted for the high performance heating element option. The whole system was just under a $1000 dollars. I've been studying the issue for months. Statistically, the vast majority of damage shops see is from water contamination, which sends metal from the pump to the injectors which ruins the pump and injectors. Some of the guys want lift pumps that put out more fuel cause their hopping up the rig. That's not me, I just want greater filter and water blocking capacity, and a bit of positive pressure(10 psi) that helps push the fuel into the pump. The stock AC Delco filter is a good one though. I can attest that the Fass system appears to be top quality, but if your mechanical skills are not good, you do need someone else to install it. To complete the job, the fuel tank needs to be dropped. So it is a bit of work. There's a good many youtube video's that show the job. If you buy it on Amazon, there is no warranty, so I bought it directly from Fass then they warrant it. There's not that much difference in the price. Shipping for the whole thing was only $16 bucks.

[grindstone01]

Originally Posted by A Don

I have a 2015 Chev Duramax with 145000 miles on it. It is running perfect and I would like to keep it that way. I am becoming more alarmed by the horror stories of the fuel pump blowing up. Has anyone here replaced one with lots of miles on just as a preventive measure? I wonder what the cost would be?

thanks
Don

My son had a 02 Duramax with 500k+ and I had a 06 Duramax with 310k+ and neither truck ever had any injector pump problems. The key is to change the fuel filter often, 10k for our trucks. We ran a lot of miles doing Hot Shot Trucking. Save your money and just follow the maint schedule for the truck.

[Kraken]

There is a particular problem with the 2011-2016 CP4 pumps, which are redesigned from the prior(I assume) CP3 pumps. Some guys are just outright ditching their CP4 pump, and going back to the CP3. Here is a technical article on the issue.

https://www.injectorsdirect.com/dura...ical-bulletin/

[grindstone01]

Originally Posted by Kraken

.............
https://www.injectorsdirect.com/dura...ical-bulletin/

That is not a GM Technical bulletin! This is a company promoting/selling aftermarket parts for their profit. If someone is concerned, it would be best to talk to your local dealer/service rep.

[Kraken]

Originally Posted by grindstone01

That is not a GM Technical bulletin! This is a company promoting/selling aftermarket parts for their profit. If someone is concerned, it would be best to talk to your local dealer/service rep.

I realize that Grind, but I do think the issue is real. I wonder what changes were made to the fuel pump/system for 2017? The issues with the CP4 are all over the Duramax forum. It seems that pump is far less tolerant of any contamination. I do respect you as an automotive engineer. One thing on my filter head I don't like is that cheap plastic bleed screw. There is an air conditioning line in the way to tighten it, so when you go at it crooked with a screwdriver it starts to get get boogered up. A cheap plastic screw protecting a $10,000 pump. I mean geez, why couldn't that be made of metal? I do see metal ones for sale on Amazon, but you spend good money on a truck that you need to spend more money on to make it right. Don

[grindstone01]

The plastic screw is just for bleeding the air after a fuel filter change and should survive the 20/30 uses over it's design life. (Can you reposition the AC line?) It's true engineers could have used a brass or gold screw but that in turn would raise the price of the truck. It's all about compromise with every part on a vehicle between cost and use. Engineers have the ability to way over design a part, but the end result would be a vehicle too expensive for most consumers to buy. Them little part cost add up fast.
I also occasionally visit the Duramax forum, keep in mind that the 98% Duramax owners that are not having problems usually don't post.

[Kraken]

I can't move the AC line, but I could reach it with a 1/4 inch drive with a wobble extension as long as I'm gentle with it. I do see aluminum and even a brass replacement available online. Oreilly's has the brass one. It's a Dorman part. Thanks for your input. Don

[phfkef]

Originally Posted by Kraken

I realize that Grind, but I do think the issue is real. I wonder what changes were made to the fuel pump/system for 2017? The issues with the CP4 are all over the Duramax forum. It seems that pump is far less tolerant of any contamination. I do respect you as an automotive engineer. One thing on my filter head I don't like is that cheap plastic bleed screw. There is an air conditioning line in the way to tighten it, so when you go at it crooked with a screwdriver it starts to get get boogered up. A cheap plastic screw protecting a $10,000 pump. I mean geez, why couldn't that be made of metal? I do see metal ones for sale on Amazon, but you spend good money on a truck that you need to spend more money on to make it right. Don

This article will show you the many changes made. Look at picture 43 for change in pump to Denso;
http://www.trucktrend.com/how-to/eng...he-duramax-l5p

[Kraken]

Originally Posted by phfkef

This article will show you the many changes made. Look at picture 43 for change in pump to Denso;
A Peek Inside the Duramax L5P

Thanks phfkef, a very nice article. I think Gale Banks will find area's for further improvement perhaps.