6.6 Duramax guys....step inside....

[mrlawler1]

Came across a '15 model crew cab ltz with low miles for a gas engine, much less a diesel motor. Former owner complaints, model complaints...stay away from the 15 models? Never again, buy again in a heartbeat....? What say you....? Any info is appreciated....thanks fellers...

[Commanchejoe]

Duramax is the way to go if you want a diesel, just stay away from the dodge Cummins, they're the biggest POS I've ever had to try to use, and I've had them all, nothing but Duramax for me, power strokes are hit and miss after the 7.3, it was solid

[greg88]

Install finer micron pre filter with water separator and don't turn it up an easy 300,000 mile motor.

[yetti462]

I've borrowed a buddies Duramax and it was much nicer than the 7.3 I used to run. I wouldn't be a bit shy on a duramax.

[gleninaz]

I have a 2015 with 119000 miles and it is a beast. Pretty good mileage and I towed a 15000# fifth wheel 1400 miles and it was perfect. Lots of power and didn't really feel anything when pulling it. I love the truck and it is a good one.

[seagoo]

Research CP4 pump issues and decide. This year/model Duarmax has one. Can be extremely costly if it fails.

[Ckfishin]

The cp4 is the issue with those trucks when they come appart they will give you a nice +-10k bill to fix.

I have had an 07 LBZ and I currently have a 2019 L5P.

The L5P they took the cp4 off and went to an HP4 setup.

[Whistler]

I have a 2016 duramax with 80K. It's been a good truck. Only issue I've had was the TCM failed and was $700 to replace. You will hear a lot about the CP4 and I'm not knowledgeable enough to dispute it (something to due with viscosity of US diesel vs European diesel Bosch designed the pump to handle). Anyway, I think most of the folks who have concerns with the cp4 fuel pump are ones who are heavily modded. They do sell boost pumps and such to help prevent the the CP4 problem but I don't know how wide spread the issue is if you are bone stock like me.

[Ckfishin]

I have a 2016 duramax with 80K. It's been a good truck. Only issue I've had was the TCM failed and was $700 to replace. You will hear a lot about the CP4 and I'm not knowledgeable enough to dispute it (something to due with viscosity of US diesel vs European diesel Bosch designed the pump to handle). Anyway, I think most of the folks who have concerns with the cp4 fuel pump are ones who are heavily modded. They do sell boost pumps and such to help prevent the the CP4 problem but I don't know how wide spread the issue is if you are bone stock like me.

They literally make a kit to save the fuel system on stock trucks when it comes apart.

Ford

https://ssdiesel.com/product/ford-6-...pass-kit-2011/

Chevy

https://www.alligatorperformance.com...iABEgI5VPD_BwE



This is what they do for the duramax because there is room to swap back.

https://www.dieselpowerproducts.com/...ramax-lml.aspx

[rboren]

Put an Airdog filter system on it and keep the original tune. Yes the pump can fail but most don’t. Ford used the same pump on several models. I know of one that failed. Bill was 12,000$. I would not be afraid of it if it has maintenance records and filters change regularly.

[Ckfishin]

Here is a thread on the cp4

https://www.duramaxforum.com/threads...ilure.1005243/

[yadkincustomlures]

The LML's aren't terrible engines other than the fuel pumps. As mentioned above that can be a catastrophic failure. When the pump goes you get little shavings of metal in all of the fuel system. This means you will have to replace the lines, rails, injectors, and drop/clean the tank. If you buy that truck I would at minimum install an aftermarket lift pump. Best fix would be to get rid of the CP4 entirely.

If you are looking for creature comforts and ride quality the duramax powered trucks usually will win due to the IFS. This is also a curse if you ever use your truck offroad. For on road pleasure/comfort use they are great trucks, for heavy work use and offroad applications they leave a lot to be desired.

[Chris225]

The cp4 is the issue with those trucks when they come appart they will give you a nice +-10k bill to fix.

I have had an 07 LBZ and I currently have a 2019 L5P.

The L5P they took the cp4 off and went to an HP4 setup.

What year did they get rid of the cp4?

[Ckfishin]

What year did they get rid of the cp4?

Denso HP4 was used starting in 2017.

[DaveBrabec]

My 2018 has been the best truck I’ve ever owned or towed with. On a 1000 mile trailer trip in Oregon as I type.

[Meadows]

My 2016 Duramax was an absolute beast. Never had one complaint, and put 150K on it. Passed it down to one of our Superintendents when I got my new 2021 Duramax and it's been just as good.

[RFSims]

I have a 2019 L5P and buddy has a 2016 LMLwith the CP4 fuel pump. The Cummins 6.7 2019-present and Ford power Stroke 6.7 2011-2022 also use the CP4 fuel pump. There are many more running than failing. If one believes the internet there should be multitudes of Duramax, Cummins, Power Stroke trucks on the side of the road. Yet I see very few if any.

According to Bosh, globally there are over 60 million CP4 produced. Over 600,000 LML Duramax engines have been produced.

Had I rather have a 2017-present L5P? Yes. Would I be afraid of a LML? No. My buddy with the 2016 pulls a 5th wheel Cougar all over the country with no problems. Will his engine grenade the next time he starts it? Maybe, but probably not. Will my L5P grenade the next time I start it? Maybe, but probably not.

[mrlawler1]

Thanks fellas.. Will do a little more research into the truck for sure..

[mactlman]

Airdog will save it and maybe a cp3 and a tune later!!