Lets generate a list of bad engines to avoid.

Not on the Hass train …
During the time I had AFM only - Clinebarger stated the hardware was the same on 5W30 mills - so at the end of the warranty - went to 5W30 and installed the plug-in disabler …
With my DFM mill - took a dealer warranty with them doing the oil - but likely to bump it up at some point …
The DFM remains active …
I saw a “Range” disabler for both AFM and DFM. Yep, not sure what the number of failures are with DFM with millions of engines made and GM’s reluctance to let go of the idea.

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I'd add Kia 2.0 engines to the list, but only the years that they used the GDI variant. Believe it was 2014 to 2019. The non GDI years seem rock solid .
 
Here is a screen shot from a 2025 Silverado ad. The turbo V-6 gets AFM and the 5.3 and 6.2 get DFM. Since 2018 when the 5.3 and 6.2 got DFM somewhere over 2 million of the DFM engines have been manufactured. I still haven’t seen any statistics on their failure rate and invite anyone to do so. I keep hearing rumours about class action lawsuits but need to see the results. Meanwhile the 2025’s are out and they still have DFM.


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With engines within the last 10ish years or so, you might need more of “what’s still good” thread instead.

I swear many of these engines are meant the fail anyways- to the average consumer.

I can use the 1.5 Ecotec as an example.

I’ve had no issues with mine in the 6 years I’ve owned it. Granted, it gets frequent oil changes, and is not beaten like a mule. My friends (who might know a little something about cars) have had similar experiences.

Now I’ve had a few co workers with a Malibu and the Equinox with nothing but problems. The Equinox is lucky to see 10k oil changes, and the Malibu is driven like it was stolen. They are treated like the cars of old, when you could get away with that. Tech now does not like abuse. While it is true they are made cheaper, with a little care they can still go for a while……
 
I have quoted and left the parts the I feel make this engine “a bad engine”. I know this is down to personal opinion and for me putting a coolant pump inside an engine, especially inside the timing casing, is exactly what makes it a “bad engine”. A coolant pump will not last indefinitely and to have to perform the level of work that it requires to replace the pump on this engine, regardless of if you catch it early and have it fixed before further damage occurs, is a repair bill that most people will be unhappy at having to swallow.
Ford botched the engineering on it somehow.

When my Nissan VQ30DE water pump failed (also located inside timing cover/driven by chain) it leaked through the weep hole, but coolant exited externally and was very obvious. Nissan also kindly placed two stamped metal plates covering openings in the timing cover that allowed access to the chain tensioner (to loosen) and the water pump. Replacement was < $60 and about 3 hours of my time. I should note this is also a transverse V6 engine crammed into a FWD car.

The water pump location in itself is not the problem.
 
What would be an acceptable failure rate of a current engine design? About 800,000 Silverados and Sierras roll of the assembly each year. Probably 500,000 have DFM but if someone has better data we’d like to hear it. If 1% of the engines failed within the first year that would be 5,000 failures. If a dealership had a truck in the shop and fixed it in one day, and was open 5 days a week, they could process 260 trucks per year out of one bay. That would mean almost 20 dealerships would fixing a failed DFM engine in one bay, full time. Do we think this is the situation? If not, how bad is it? GM’s power-train warranty is 5 years IIRCC. So independent shops would not be seeing them until year 6. So what is the failure rate by then. We need to see real numbers. In those 5 years there would have been 2.5 million engines made and at a 1% percent failure rate 25,000 trucks would need fixing. That would catch a lot of attention, even at 1%. Is that what is happening?
 
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When an independent mechanic calls up a Kia dealer and asks if there are any of a certain model engine in stock and the dealer says " We have 20 new ones that just came in." I think that qualifies to be on the list.

Basicly, if the mechanics at a dealer had become use to replacing a certain engine, it probably belongs on the list.
 
My list includes Fords with internal water pumps. Those being 3.5, 3.5 Ecoboost and the 3.7. Second is Fords 2.7 which has a oil submerged rubber cogged belt which drives the oil pump.
Lots of older cars ran the pump from the timing chain like the nissan vq or the belt like toyota MZ or Honda D, B etc etc, all are loved and have proven their worth.

Pretty sweet setup, it fails at about 150,000 miles, good time to replace the whole timing setup too,
 
I'd add Kia 2.0 engines to the list, but only the years that they used the GDI variant. Believe it was 2014 to 2019. The non GDI years seem rock solid .
The 2020 Kia 2.0 MPI have-had more engine failures than possibly the 2018 and 2019 2.0 GDIs combined.

The engine failures are due to problems with the piston oil rings, which may not have been properly heat-treated, leading to excessive oil consumption and potential engine damage, resulting in these failures. The manufacturer claims only 1% of those manufacturered are subject to replacements. But the numbers are nearly likely in the double-digit percentages.

There's only two other 2020 2.0 MPIs in my subdivision, other than mine. Both have seen engine replacements. My longetitivity rate (currently 32k) may be because of my BITOG knowledge and use of top-tier oils. Yes, our engine failure may appear inevitable and may occur any day. But my overly-high maintenance practices seem to have 'at-least' delayed the death of my wife's engine. She loves the vehicle and won't part with it.
 
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