Lets generate a list of bad engines to avoid.

I hold Clinebarger's posts as 100% fact based upon my experience but I remember so many people thought AE Hass's thin oil posting much more than opinion
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 …
 
For example the Ford 3.5L Cyclone v-6 engine in n/a transverse applications. The water pumps are expensive to replace (internal the the front cover) and if you don't pay attention to the warning signs, the leak issue could result in a ruined engine. The reality is that water pumps don't last forever; every water pump can be expected to fail at some point. But if you don't catch the impending failure, the engine is a gon'er.

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.
 
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.
The internal water pump is not a new concept. One of the bigger examples was the GM Ecotec, which never developed the same water pump related reputation. Internal leaks were not a problem and they were perfectly serviceable.

Nothing wrong with the basic concept, it's just poorly implemented in the Ford's case.
 
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.
only transvers 3.5 have internal water pumps. hundreds of thousands of trucks have great 3.5 ecos.
 
I think the owners of the old IDI 6.9L engines, as well as the 7.3L PSD (T444E) engines, would disagree.
+1 small.webp

I've owned two 7.3 PSD engines. Very reliable and dependable.
 
These threads are useless for figuring out whats good and whats bad. We are all going to have our own anecdotes about good luck with xyz engine and bad luck with pdq engine. I had the epitome of two 'bad' engines... a turbo Mazda rotary, and the aluminum block/iron head Frankenstein monstrosity Mercruiser 3.7 four cylinder in my boat. I took the turbo rotary to an almost unheard of 125,000 trouble free miles, and I mercilessly beat the Mercruiser like a rented mule for 10+ years and rarely had an issue at all with either.

My trusty, rock solid Hondas? HAHA nope. Both the 4 cyl and the in-production for, how many years now?..... 3.5 V6 suffered flattened cam lobes, ignition issues, both leaked oil like there was no tomorrow, the 4 cyl drank more oil than gasoline, the V6 spit plugs and melted coils.... the problems just kept coming.

Both anecdotes completely opposite of the general trends. As much trouble as the Hondas were, if someone came to me and said they were considering either a 3.5 V6 Honda Pilot, or a turbo Rx7, which one would I recommend.... I would scream run away from that Rx7 as fast as they can, until they fell over and had a heart attack. Then get up, and run a whole lot more, and go buy the Pilot. Even though that goes completely against what my own experience was.

Ford straight sixes, Chrysler slant 6's, Chevy small blocks.... had them all at some point, and had nonstop issues with all of them. The older guys will tell you those engines were rock solid.

My Kia? My Mazdas with the older guy boogeyman GDI's? Literally the only nonscheduled items I've had to replace is two coils, with over 300,000 combined miles between the three.

I stand by my previous comment. These threads are useless.
 
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Personal opinion, but I would never own anything with the cylinder deactivation technology on it. And I don't care who makes it (e.g., GM AFM, Honda VCM, Chrysler MDS, Toyota DFM, etc.). It is a problem waiting to happen in any application. The industry should have learned their lesson in the '80s from Cadillac's foibles with the HT V8-6-4 and Northstar motors.

The Ford 5.0 F150 now has cylinder deactivation. It can be disabled in various drive modes and is mechanically simple and trouble free. Interestingly, Ford updated the piston ring package to prevent oil consumption and wear related issues with this system. So the expectation is very long trouble free life.

I am not aware of any 5.0 cylinder deactivation related problems. Seems to be a very tough engine.
 
Good thread. When it comes to a topic like this what I see is folks have no idea what makes a good design or not.
Engines? I've seen some that could be great designs if they did the correct things to begin with. Where most all fall short is not following what the old timers figured out 60 some years or more, as far as how to prevent the many issues that are happening today.
If I or whom ever mentions these correct things there are the ones that support the newest and supposed greatest manufacturing garbage that is done today. In a nutshell all modern auto engines are mostly cheaply made junk now. Some things on some of them are done very nice, but then they mess it up on something else. The engines now are not being made to last, the manufacturing techniques and materials are to build them fast and inexpensively.
Yeah got to love the stupid things they do now, like coolant pumps that can fill the oil pan, rubber belts running an oil pump. Sorta like designing something that is supposed to break at some point in time. Using RTV instead of gaskets that will in time leak, plastic ford one time use oil pans, and all the other plastic garbage that will degrade and fall apart. Its strange that not many manufactures can make a roller lifter that will last long, when they have been used for years on some aircraft engines, diesel industrial engines etc. for close to 100 years or so. Why is that?
 
Every MDS Hemi.
And yet MDS hasn't been a problem for FCA? The lifter failures started after VCT was added, the pre-VCT engines (that had MDS) didn't have lifter failure and the lifter issue itself (in both FCA and GM applications) often occurs on non-MDS/AFM/DFM lifters. Same failure model as Ford has with the 7.3L.


Didn't they switch cam manufactures or something around then? Metallurgy issue
 
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