2018 Chevrolet Silverado 2500 HD/Duramax/Allison WTF Moment!!!!

dbart

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So, yesterday, Sunday 08/15...my wife and I are headed to my mom's in Arcadia. We are on the 57 NB just before the 60 fwy when all the sudden my truck starts shaking...BAD! No it's not a tire shake, I just put brand new tires on.

This was different...I'm starting to feel like I'm losing power! No engine code...everything is reading fine.

I pull over at Pathfinder and shut it off. i wait a minute then start it up...it's just shaking really bad so I pop the hood while its running thinking a Motor mount had failed or something.

Nope all looks good...no leaks underneath, no visible damage that I could see looking under the truck!

So I shut if off and call AAA.

Tell them what I have and to send a flatbed cause this thing is heavy.

Get towed to Simpson Chevrolet in Garden Grove, where I bought it and drop it off.

Saw Chris, the salesman who sold me the truck and my wife's Camaro...he said, hey Dale what's up how have you been?

Well.............and I tell him what's going on. he was like, oh man...so sorry!

He said Service get's in at 7:00am and they'll take care of me and if I need anything to call him!

So, 7:00 am this morning I'm at the dealer. I tell the guy to start my truck and he does.

He's like, whoa...that sounds like a REALLY BAD misfire but weird there's no codes being thrown!

Yeah...I know.

Anyways, he's trying to get me a loaner and they'll dig into it!

Only 58K miles on it, I know I have full Bumper to Bumper 100K mile warranty plus the drivetrain has factory 100K warranty on it.

So, WTF???

I have just read that there have been some issues with the trans and Aluminum Drive-shaft....maybe the torque convertor..?

This will be interesting, but I pray it's covered under warranty.

And, no I didn't fill it with Gasoline.  :lmao:

Any Chevy guys here with any thoughts to this?

:dbart:

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Bummer dude, I have no idea :dunno: ....interested to hear what they find.

 
Never mind.  Was thinking CP4 failure but the 2018 has the C5P

 
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Really strange.

When the guy dropped the truck, I had to back it up farther...it barely moved.

Then this morning...it barely started but then you could just feel the whole thing shaking.

 
My money is on CP4 fuel pump failure.  Wouldn't own a truck that has this pump and is out of warranty.  Ticking time bomb.  

Lets just hope I am wrong.
Crap, well I bought the extended Bumper to Bumper warranty, so hopefully they'll cover it!

UGH!

 
Just looked up and the CP4 is on 2012-2016 trucks...mine is 2018 with the L5P motor. Hopefully different Fuel pump.

 
My money is on CP4 fuel pump failure.  Wouldn't own a truck that has this pump and is out of warranty.  Ticking time bomb.  

Lets just hope I am wrong.
The newer trucks use a L5P pump. Don't think it will be part of the previous years failures and current lawsuits.

CP4 is Bosch

L5P is Nippondenso

 
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@dbart

I've noticed on my truck any engine issue tended to cause the Stabilitrac system to go into fault or throw a message on the display. I am surprised it didnt for you or maybe it was a quick flash and you didnt see it.

My bet is it will be covered and something that just doesn't make any real mechanical sense. These new trucks are overly complicated.

 
@dbart

I've noticed on my truck any engine issue tended to cause the Stabilitrac system to go into fault or throw a message on the display. I am surprised it didnt for you or maybe it was a quick flash and you didnt see it.

My bet is it will be covered and something that just doesn't make any real mechanical sense. These new trucks are overly complicated.
You know I did see that...I'll Luis right now1

Thank you.

 
That sucks! Sorry to hear man. Good luck, your warranty most likely covers everything mechanical. You should be good, but sucks to even go through that. 

 
You know I did see that...I'll Luis right now1

Thank you.
It will be recorded. They will see it. One thing I have been doing is every time I've had an issue, I call into Onstar. Onstar will record the issue and email you the call in with the issue. Its a nice way to record whats happening if you know what i am leaning into!

 
Good news, I called Luis...he's getting a loaner for me and having it washed so it'll be good to go in about an hour.

I told him about the Stabilitrak...and he said not to worry they are going to dig into this.

I'll keep you posted as this is pretty weird!

Thanks for all the comments and insight as to what this might be.

 
Super weird, but as others have stated your L5P has a HP4 high pressure fuel pump (and a factory lift pump), so it's unlikely it's a HPFP failure.  Not impossible, but extremely unlikely.  And, if it was the HPFP at least you have the warranty so it'll still be okay in the long run.  Hopefully they find it's some silly sensor, a bad tank of fuel (I know you said you didn't put gasoline in it, but that doesn't mean you didn't get bad diesel) or something else simple.

-TJ
 

 
dam that sucks.. biggest thing i have to worry about in my old dodge is that it has oil in it.. id still like a newer truck tho since they are so dam confortable to drive.

 
dam that sucks.. biggest thing i have to worry about in my old dodge is that it has oil in it.. id still like a newer truck tho since they are so dam confortable to drive.
I hear ya...My 2004.5 was an awesome truck, but after my wife got her Camaro in 2015 it was so nice and all the new gadgets and screen, LED lighting, blah blah blah, I knew I wanted a new truck after hers was paid off.

I love this truck and it is almost paid for and then I'd like to think that is it. Just enjoy it an drive it.

 
dam that sucks.. biggest thing i have to worry about in my old dodge is that it has oil in it.. id still like a newer truck tho since they are so dam confortable to drive.
They all have ups and downs.  I have an '11 which is of course now "old" but also had all the emissions stuff cat/DPF/DEF/SCR/F-ME... wait that last one might be wrong. 😉 Legend has it all that stuff "fell off" around 5k miles (at 127k now) and the truck has been great (*knock on wood*).  I did replace the CP4s at ~100k miles as preventative maintenance and I've always run a lift pump, additional filtration, and good fuel additives. 

-TJ

 
Would a bad injector cause symptoms like that?
Not sure? From the way it was acting and shaking...I wouldn't think so. It seemed like a drivetrain issue for sure.

 
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