2024 6.6 gas 28000 engine failure

MORSNO · April 29

18 hours ago, AndrewF said:

The 6.6 gas has been one of the more reliable engines produced lately. Interested to see what the dealership says but hopefully you're still under warranty so it'll get taken care of.

And I'm under the impression it is not a reliable engine, the only engines with a worse track record are the AFM engines used in the 1500 series. I've owned nothing except Chev/GMC trucks my entire adult life, but seriously leaning to Ford SD trucks with very reliable 6.8 & 7.3 SD engines along with a more dependable transmission.

newdude · April 29

32 minutes ago, MORSNO said:

And I'm under the impression it is not a reliable engine, the only engines with a worse track record are the AFM engines used in the 1500 series. I've owned nothing except Chev/GMC trucks my entire adult life, but seriously leaning to Ford SD trucks with very reliable 6.8 & 7.3 SD engines along with a more dependable transmission.

Godzilla eats cams but I guess you missed that part.

L8Ts that come in at work have been reliable. We've only replaced one engine in a customer truck in the 6, going on 7 years its been out. Maybe 2 or 3 came in for oil consumption monitoring.

Edited April 29 by newdude

BuckWallace · April 29

1 hour ago, MORSNO said:

And I'm under the impression it is not a reliable engine, the only engines with a worse track record are the AFM engines used in the 1500 series. I've owned nothing except Chev/GMC trucks my entire adult life, but seriously leaning to Ford SD trucks with very reliable 6.8 & 7.3 SD engines along with a more dependable transmission.

What gives you the impression it's not a reliable engine? Honest question.

MORSNO · April 30

22 hours ago, BuckWallace said:

What gives you the impression it's not a reliable engine? Honest question.

Everywhere I go all I see is that a huge percentage of them use oil like its gasoline. Adding a quart of oil every 1,000 miles is not acceptable for a quality engine.

newdude · April 30

26 minutes ago, MORSNO said:

Everywhere I go all I see is that a huge percentage of them use oil like its gasoline. Adding a quart of oil every 1,000 miles is not acceptable for a quality engine.

So a few people on the internet out of the hundreds of thousands sold leads you to believe that. Got it.

Chuck FB · April 30

1 hour ago, MORSNO said:

Everywhere I go all I see is that a huge percentage of them use oil like its gasoline. Adding a quart of oil every 1,000 miles is not acceptable for a quality engine.

I can't claim that what you have seen said is entirely wrong as more engine platforms have gone over to lower tension rings and that has caused increased oil use as a result of that idea of reducing friction but the side effect of more oil slipping by the rings. However even on this forum there are those that have done a fair bit of towing with their trucks and not experienced high oil use along with some that have had higher than what has been considered normal oil consumption. Why the differences is a good question and I realize that the internet can drag out more of the bad then the good due to those that are not having an issue don't have reason to talk about something that is not a problem vs those that have a problem and are openly spreading around their frustration over an issue.

All I can say so far with certainty from my short term experience with my own truck given that I have relatively few miles on it and have not been towing with it so far, is that its not been showing up to be an oil user under my low load use conditions. I was changing the oil very frequently for the first few oil changes because of wanting to do the best I could do flush out break in wear metals. The last oil I dumped out was from use this winter and was a 0W-30 and being used in our not so lovely Alberta winter temps and no doubt higher risk of more fuel dilution although by this spring with more moderate temps and my usual 100 mile plus round trips to town all along I can only speculate that most of any gas that may have found its way into the crank case would have gone through the pcv system. I estimated that perhaps the oil level had dropped around 1/16 of an inch in that 2500 miles and this was being parked in the exact spot each time I check the oil.

A few weeks ago I had a brief conversation with a mechanic that has run his own one man shop for years and have had him do work over the years on a prior pickup and he works on various brands of pickups and so forth ( leaves the diesel end of things to others that have the specialized equipment for that ) and his brief comment to me about the 6.6 gas is that its been doing good overall BUT with the caveat that as long as one changes the oil often. Unfortunately he never had the time to elaborate beyond that as per what happens if its neglected but I know over the years he has worked on a lot of Ford half ton pickup engines replacing the timing chain and phasers and so on and that goes back to the 5.3 and the 5.0, 3.5 etc and the biggest determining factor often was how often the oil was changed or not as so many vehicles out there are going by factory minimum service intervals and its causing a lot of premature wear on some components.

James McArthur · April 30

On 4/28/2026 at 2:28 PM, Chuck FB said:

Have you been doing your own oil changes and if so any particular oil filter brand you have been using. Also within that theme of oil changes was the oil changed just prior to this occurrence or a while back.

I am purely speculating that something mechanical either let go due to a defect and a chain reaction such as a valve dropped after a valve spring broke etc or I suppose there is a possibility that a cam or crank bearing could have turned restricting oil flow and the oil pressure would remain good on the gauge but in reality starving parts of the engine from adequate oil. I guess that remains to be seen if the dealership does a tear down or if they find a mess and determine a new engine gets dropped in and the original engine gets whisked away without a proper look.

No I don’t do my own oil changes and yes I’ve checked the oil level after each change regularly, dealer removed rollers and push rods today all look good on right bank, so going deeper tomorrow by removing head to get to lifters we will see what they find at that point!

James McArthur · May 1

3 hours ago, James McArthur said:

No I don’t do my own oil changes and yes I’ve checked the oil level after each change regularly, dealer removed rollers and push rods today all look good on right bank, so going deeper tomorrow by removing head to get to lifters we will see what they find at that point!

It’s official: dealer just confirmed this evening,

I’m to receive a new long block! The number 1 rod bearing spun putting shavings in the oil.

New 6.6 engine will be ordered in the morning.

No F-bdy Bs · May 1

7 hours ago, James McArthur said:

It’s official: dealer just confirmed this evening,

I’m to receive a new long block! The number 1 rod bearing spun putting shavings in the oil.

New 6.6 engine will be ordered in the morning.

That's honestly the first time I've heard of a 6.6 doing that.

GAMark · May 1

Same first time for me hearing this also.

James McArthur · May 3

On 4/28/2026 at 8:56 PM, No F-bdy Bs said:

Got a feeling someone is confusing the 6.2 for the 6.6.

Right or wrong dealership is awaiting approval for 6.6 to be replaced caused the 28,000 mile new engine spun #1 rod bearing and filled itself with metal, oh boy! Not feeling HD DNA at this point, anybody no how this will effect the resale value at some point.

James McArthur · May 3

Right or wrong they are awaiting approval from engineering to replace engine!

chris21 · May 3

You never did share how frequently you had the oil changed in this engine? I am also curious if the air filter was ever changed or if you used an aftermarket intake?

mjm-1957 · May 3

Make sure they replace the radiator and oil cooler lines also. The oil cooler in the radiator will be full of metal and there is no approved method to clean them. GM will bounce the claim if those are not replaced when the engine gets changed.

Chuck FB · May 3

As I believe I asked before, what the timeline was relative to the last time the engine oil was changed or any other maintenance that could have caused a foreign object to be introduced into the engine by way of the oil or the intake, including someone tampering with your truck. Also am wondering if by chance for example a small roller bearing came out of a roller lifter or one of the rockers and started a chain reaction of metal being able to get past the filter ( cold engine start filter bypassing for example ) and went through the crank bearings. I imagine it can be hard to tell after a bearing gets chewed up and sends metal around through the engine, the oil pump would have damage at that point so destroying any prior evidence. But it certainly could be a slight manufacturing mistake on the crank, the connecting rod or the rod bearing itself that eventually lead to it being spun in the con rod. I assume dealers don't spend too much time trying to sort out what could be hard to prove and if warranty covers the situation, a new engine and oil cooler system gets swapped in and life goes on.

Like others I am curious what the oil change schedule was typically like and if there were a lot of idle hours on the engine or a lot of very short runs ( potential fuel dilution ) etc at times.

I could be wrong in my thought but I rather doubt a complete/new engine replacement swap being done would affect future resale as long as the new engine is running well and perhaps some oil samples taken after its broken in to prove to you or a future buyer that its not showing any abnormal wear. The issue more so I think is when a particular vehicle platform gets a bad reputation rap like the 6.2 GM or way back with the GM gas block 5.7 diesel as buyers run the other way based purely on reputation and resale plummets as a result.