2018 LP5 Failed lifter Cylinder 5

[Rockymtnguy]

My 2018 3500 Denali was in the shop for over 20 some days for what finally was diagnosed as a failed lifter on cylinder 5. After a nightmare event dealing with a GM rep at Newby Motors in St. george Ut. I am still trying to make my way back to St. George to drive my truck. Not sure how it drives or runs until I pick it up this week. Anybody have any issues similar to this. 3800 miles and a blown lifter rod. Not sure what the depreciation is on a failed then repaired motor. 

[redwngr]

I spend way to much time following several active truck forums that follow dmax and L5P.

 

I'm only recalling one similar - it was push rod related.

 

I think you're asking is this a common failure? 

The answer would be no.  It would be rare failure rather than common.

 

Depreciation?

Trade it at 4000 miles, and I'd suspicious that there are other things you're hiding.

Trade it at 40,000 miles and I'd think the repair was an interesting note, but wouldn't give it a second thought. 

 

 

[newdude]

Very low but there is a couple reports of pushrod failure.  We had a truck in for one.  Guy had 2400 miles on it, bought it out of state.  Truck was completely fine after the repair. 

 

I'd drive the balls out of it. 

 

Hopefully they saw this and follow this to a T:
 

Quote

 

#PIP5537A: 6.6 L5P Duramax Engine Misfire Diagnosis - (Dec 20, 2017)

 

A customer may report a loss of power, misfire and/or SES light illuminated. The engine may have a rhythmic tick noise or exhibit a popping sound from the air filter box. Misfire DTCs including P0300 may be set in the engine control module (ECM).

 

Multiple root causes are possible, but in the most likely scenario, an intake or exhaust pushrod has broken at the upper cup causing no lift on the valves for that cylinder. Excessive valve clearance (lash), may also cause similar symptoms. Lastly, catastrophic damage to the cylinder cause by loose foreign debris such as a mishandled ceramic glow plug fragment can cause leakage past a valve seat. 

 

Do not replace fuel injectors for this concern.  

 

If an engine misfire with DTC P0300 is found and it can be isolated to a single cylinder, perform a compression test.

Note: Glow plugs must be discarded whenever removed, and replaced with NEW.

 

If compression less than 350 psi is measured on a single cylinder, a cylinder leakage test should be performed on the cylinder exhibiting low compression. If excessive leakage is NOT found, technicians are advised to remove the valve rocker cover on the affected side and to inspect for a damaged pushrod, damaged valve adjuster or excessive valve clearance (lash).

If a pushrod is found broken, technicians are advised to replace all pushrods on the affected bank and re-set the valve clearance (lash) for both intake and exhaust valves. Refer to Service Information (SI) for valve clearance adjustment procedure and specifications.

 

If all pushrods are intact, technicians are advised to check valve lift height and for an adjuster at the end of it's limit. This could be an indication of a rotated valve lifter. If you are able to verify that a lifter has rotated in the bore and ground away at the cam shaft, engine replacement is required.

 

If a cylinder has low compression AND high leakage rate, this could be an indication of a stuck open valve. Refer to Service Information.

Refer to Service Information for proper procedures on engine compression testing, cylinder leakage testing and setting valve lash.

 

 

[2018GMC]

That sucks op. Who wouldn’t be pissed? Unfortunately sometimes $hit happens. 

 

I would drive the crap out of it and hopefully it will be good after this. If it gives you further trouble, reach out to GM customer care and find another dealer if you aren’t happy with this dealers service. 

 

GM is sticking with the L5P. Gale banks and a few other hot toddlers supposedly influenced its design. It is still in the new generation trucks with a few minor upgrades to oil cooler, etc. 

 

Good luck and keep us updated. 

[EXSlider400]

I have mine in for the cooler line but  a rhythmic tick has also appeared so I hope it is not a lifter. Truck has 31k miles so is the L5P warrantied to 100k...and particularly this issue? 

[paauto]

17 hours ago, EXSlider400 said:

I have mine in for the cooler line but  a rhythmic tick has also appeared so I hope it is not a lifter. Truck has 31k miles so is the L5P warrantied to 100k...and particularly this issue? 

I had that tick and then changed to full synthetic oil and it went away (25,000 miles ago).  38,000 miles on mine now and all is good.  BTW, if you have some time to kill (45 min) watch this Gale Banks video.  

 

[EXSlider400]

I just switched from full T6 to semi T5.  I don’t think it’s hurting anything just me being picky.  Thanks for the video to