2016 Duramax

[wzuber]

A friend of my crew chief is thinking about selling his 2016 LTZ D-max. Has 90k miles, fully loaded from factory, leather int. Small lift on 35" tires, good maint. Records etc.
Clean truck
I'm interested in buying it to replace my 04 LB7.
What's the good and bad on this year model? Def issues? Injectors? Transmition? Any recalls on this model yr.? Please advise if you have direct knowledge or experience.
Also, what would you value it at?
Thank you.

 

[BigRedBryan]

Cp4 failure.

 

[monkeyswrench]

Cp4 failure.

X2
That's really the only issue I've seen on them out here.

 

[DuttonDave]

CP4 failure can be catastrophic !!! 10k to fix

 

[Flatsix66]

CP4 failure, They usually fail right around 90k miles.

Mine also had all kind of DEF issues, just after the warranty was up. It would always happen on a road trip and start limiting your speed until you found a dealer. Never again.

 

[wzuber]

CP4 failure can be catastrophic !!! 10k to fix

Thanks, so what's the fix. Just replace w/same or is there an upgrade?
Does adding an aftermarket lift pump solve the issue?

 

[wzuber]

CP4 failure, They usually fail right around 90k miles.

Mine also had all kind of DEF issues, just after the warranty was up. It would always happen on a road trip and start limiting your speed until you found a dealer. Never again.

Thanks for the insights
What kind of def issues did you have and what did it take to cure it?

 

[NicPaus]

Thanks, so what's the fix. Just replace w/same or is there an upgrade?
Does adding an aftermarket lift pump solve the issue?

CP3 swap. I have a 2015 work truck Duramax. Hopefully never have to deal with it as it only has 16k miles.

 

[ChrisV]

Cp3 swap and tune. Good trucks

 

[Chili Palmer]

I got over 310k on my CP4 before I sold it, but I also used Optilube XPD at every fill up.

 

[Albert]

They wont ship to Cali for the CP3 swap I will need one done

 

[Maw]

I have the '16 GMC Denali and one of my sons has the '16 Chevy Duramax, both 4X4s. I've had the DEF tank replaced on mine under warranty, my son has had zero problems with his. I'm at 106,000 and he's about the same, maybe a bit less. 90-95% of the mileage is freeway back and forth to Havasu so not heavy usage.

 

[wzuber]

I have the '16 GMC Denali and one of my sons has the '16 Chevy Duramax, both 4X4s. I've had the DEF tank replaced on mine under warranty, my son has had zero problems with his. I'm at 106,000 and he's about the same, maybe a bit less. 90-95% of the mileage is freeway back and forth to Havasu so not heavy usage.

interesting, thanks for the info. Did the tank split or what happened that caused to be replaced?
what's the standard factory warranty on these? 3yr/36K miles? did they offer a 100K mile warranty option at the time?

 

[wzuber]

Cp3 swap and tune. Good trucks

cp4 is the fuel pump correct? located in the intake valley like the lb7?
did cheby change to a push type fuel system (fuel pump in tank or low on frame rail) from the draw/suck fuel system of the earlier models like my LB7?

 

[wzuber]

can a person pull the dealer maintenance history records from a carfax type system or does it have to go to a dealer for that? Can my buddy pull that from his repair shop?

 

[hawgty55]

@90k get a warranty and still might be under manufacturer warranty. And if its not a CA truck just delete it. Bought an 18 L5p witch is extremely expensive ti delete compared the LML. I wish i had known that before my purchase.

 

[sintax]

cp4 is the fuel pump correct? located in the intake valley like the lb7?
did cheby change to a push type fuel system (fuel pump in tank or low on frame rail) from the draw/suck fuel system of the earlier models like my LB7?

correct, its the HPFP (high pressure fuel pump) that is located on the engine. I dont think GM has ever run a lift pump, i know my 07 doesnt have one.

as far as the CP4 to CP3... yea everyone has ditched the CP4 that was using it. They've all moved either back to a CP3 or to a Denso HP4 (GM 2017+) corrected

CP4 to CP3 runs around 4k for the pump and associated shit, as long as your CP4 is good. If the CP4 has gone to shit, youre looking at 10-12k to R&R the whole mess

 

[hawgty55]

cp4 is the fuel pump correct? located in the intake valley like the lb7?
did cheby change to a push type fuel system (fuel pump in tank or low on frame rail) from the draw/suck fuel system of the earlier models like my LB7?

I believe in 22 they did. Mines an 18 and still below the rail and fill under hood. Thought you were referring to the def system.

 

[hawgty55]

correct, its the HPFP (high pressure fuel pump) that is located on the engine. I dont think GM has ever run a lift pump, i know my 07 doesnt have one.

as far as the CP4 to CP3... yea everyone has ditched the CP4 that was using it. They've all moved either back to a CP3 or to a Denso HP4 (GM 2020+)

CP4 to CP3 runs around 4k for the pump and associated shit, as long as your CP4 is good. If the CP4 has gone to shit, youre looking at 10-12k to R&R the whole mess

The new L5p 17 to present now have lift pumps.

 

[Mikes56]

I’ve got a 2016 dually Duramax that I bought new in 2015. I use it to tow my boat and toy hauler only. 36,000 miles and the only problem was the DEF tank heater a few months ago. Dealer repaired under a “special warranty” for free.

 

[Albert]

My DEF tank was replaced under warranty as well, I was told if the truck sits the DEF crystallizes .

 

[monkeyswrench]

@90k get a warranty and still might be under manufacturer warranty. And if its not a CA truck just delete it. Bought an 18 L5p witch is extremely expensive ti delete compared the LML. I wish i had known that before my purchase.

I may or may not have seen a 22 go on a diet last week...Holy shit that's expensive! I asked about cost, because it was the newest I'd seen. Before price was said, he said "Don't talk about this around his wife..." Then he told me

 

[sintax]

I may or may not have seen a 22 go on a diet last week...Holy shit that's expensive! I asked about cost, because it was the newest I'd seen. Before price was said, he said "Don't talk about this around his wife..." Then he told me

how are they getting around the ecu lock on the new ones?

I was looking into a CT4-V Blackwing and tuning, they're hit with the same ecu limitations.

 

[eand28]

how are they getting around the ecu lock on the new ones?

I was looking into a CT4-V Blackwing and tuning, they're hit with the same ecu limitations.

Switch ecu’s with an unlocked one

 

[monkeyswrench]

how are they getting around the ecu lock on the new ones?

I was looking into a CT4-V Blackwing and tuning, they're hit with the same ecu limitations.

I ain't sayin' shit...but I heard a guy may order a new, blank ecm, "clone" it, then perform some E wizardry hooked to a laptop, then swap it in.
Keep every damn part and the stock ECU in the garage, should they be needed.

The damn ECU is tied into the BCM for everything! Heads up display to butt warmers I think.

 

[DWC]

Ours has 140,000 miles. Couple injectors, def heater but nothing else major. It’s been a very good truck.

 

[Racey]

I got over 310k on my CP4 before I sold it, but I also used Optilube XPD at every fill up.

The dry ass ULS fuel kills the motors, i believe the automakers were in cahoots with the EPA on the fuel swap from 500ppm sulphur to 50ppm as they knew it would just mean selling more trucks.

You don't hear of anything doing 1 million miles now, 12 valve Cummins and early 24 valve 5.9s you heard about them all the time.

You gotta run fuel additives if you want them to last,

 

[Dcb.blake]

Cp4 failure.

X50 and mileage wise it’s in the time where they go.

To do right, shop labor about 12k.
New cp4 (swap it to cp3 if you can)
New injectors + lines
Clean and flush tank which is the most important part



A lot depends on the quality of fuel. No way of telling if they are going to shit the bed.

Another option is to just change the cp4 before it goes out.

Shop labor about 5kish pending on what shop. Again pending where you are for smog I would go to a cp3 to eliminate the issue.

Motors are great, trans great. I do like the interiors as well and they seem to be better than the newer ones as far as having the solid feel.

 

[n2otoofast4u]

All you hear is the bad, and most is from guys who “hear about it”….. 15 GMC Duramax here, been SUPER reliable. Don’t believe all the nonsense, they can be great vehicles.

 

[monkeyswrench]

All you hear is the bad, and most is from guys who “hear about it”….. 15 GMC Duramax here, been SUPER reliable. Don’t believe all the nonsense, they can be great vehicles.

That's the thing, I only see crap when it breaks I know there are more trucks out there that I don't see, than those I do. The first one I worked on was a complete pump failure at 100k. It got one of everything. It was probably abused passed the SES light for low pressure or performance before they tool it seriously.

 

[Maw]

interesting, thanks for the info. Did the tank split or what happened that caused to be replaced?
what's the standard factory warranty on these? 3yr/36K miles? did they offer a 100K mile warranty option at the time?

DEF tank heater failed at around 95,000 miles. The crack in the tank was noticed during removal so the dealer took care of both issues under warranty. I had purchased an extended warranty when I purchased the truck, but the DEF issues were covered by an extended factory warranty involving emissions equipment.

 

[fastenuff3]

DEF tank heater failed at around 95,000 miles. The crack in the tank was noticed during removal so the dealer took care of both issues under warranty. I had purchased an extended warranty when I purchased the truck, but the DEF issues were covered by an extended factory warranty involving emissions equipment.

Any emissions problems have a 10 year warranty.My buddy purchased a 2015 cheap with pump failer and GM has a complete kit for under 2000 and he fixed it his self in a weekend. He is a carpentor by trade.