3.6L ENGINE RELIABILITY

mwilk012

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Plastic parts are the worst 'advancement' of the modern engine.
I have seen plastic cooling parts fail across all makes. It doesn't matter how good the engine is if a $20 plastic pipe fails.
The plastic only failed after the engine was experiencing significant failure caused by a metal part leaking.

however, we are going back in with a new aluminum oil cooler/oil filter housing. I am leery of Dorman products but this one seems pretty nice.

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DanW

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In spite of all the plastic, these engines are far more reliable and durable than the old engines my Dad and Grandpa loved that had nearly all metal parts.

The famous viral Pentastar with 625k miles on it had plastic parts that did pretty well, by my estimation.
 

CarbonSteel

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In spite of all the plastic, these engines are far more reliable and durable than the old engines my Dad and Grandpa loved that had nearly all metal parts.

The famous viral Pentastar with 625k miles on it had plastic parts that did pretty well, by my estimation.
Agreed! All mass produced engines have the potential to fail in some way or another and though there are some engines with inherent design issues, by and large most are very reliable given ALL of the constraints they are required to meet.

Proper maintenance at decent intervals goes a LONG way to ensuring engine longevity.
 

CarbonSteel

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3.6L engine completely unreliable
After 36000 miles, the engine started knocking
I had to replace an engine with the same engine type
At the cost of $ 8600 (Long Block without the all covers)
The service center does not take responsibility

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Given there are more than 10 million of these engines produced and given that most automotive manufacturers have a failure rate of about 1%, (and while it sucks if it happens to you), there could be over 100,000 engines fail before it even crosses the line of abnormality.
 

gerlbaum

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All the engines from modern manufacturers follow ISO 9001 standards which includes a failure rate (I think it must be below 0.1% or something). I’m not an engineer and I am sure one could school me or correct me but I know all auto manufacturers do follow that standard.

The 10 failure stories or issues you read about on the internet are not indicative of the overall engine reliability. I think AAA said some like 93% of all car issues are electronic and not mechanical - if that helps any.
 

DanW

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Agreed! All mass produced engines have the potential to fail in some way or another and though there are some engines with inherent design issues, by and large most are very reliable given ALL of the constraints they are required to meet.

Proper maintenance at decent intervals goes a LONG way to ensuring engine longevity.
So true! I've had some engines with very bad reps that never showed me an issue. One was the Toyota slugde-o-matic 3.4 in my mid 90's 4 Runner. Mine never had the issue. I was running a top full synthetic oil that had much greater resistance to sludging, so when the looked at it as per the recall, they came back and said it not only was fine, but looked exceptionally good. I was doing the standard 3,000 mile oil changes back in those days. That vehicle then went to my Dad who ran it out to 200k or so before selling it. He continued the same maintenance practices and it never did have an issue and ran perfectly.
 

CarbonSteel

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All the engines from modern manufacturers follow ISO 9001 standards which includes a failure rate (I think it must be below 0.1% or something). I’m not an engineer and I am sure one could school me or correct me but I know all auto manufacturers do follow that standard.

The 10 failure stories or issues you read about on the internet are not indicative of the overall engine reliability. I think AAA said some like 93% of all car issues are electronic and not mechanical - if that helps any.
Internet amplification always carries bad news at light speed, good news not so much...
 

CarbonSteel

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So true! I've had some engines with very bad reps that never showed me an issue. One was the Toyota slugde-o-matic 3.4 in my mid 90's 4 Runner. Mine never had the issue. I was running a top full synthetic oil that had much greater resistance to sludging, so when the looked at it as per the recall, they came back and said it not only was fine, but looked exceptionally good. I was doing the standard 3,000 mile oil changes back in those days. That vehicle then went to my Dad who ran it out to 200k or so before selling it. He continued the same maintenance practices and it never did have an issue and ran perfectly.
I only do 5K changes on my 3.6L. I see zero reason to try and eek out every drop of oil life and to what end anyway--to have bragging rights? I have done my fair share of extended OCIs (15K+ miles), these days I would rather just know the engine is being maintained as well as it can be at a decent cost point.
 

DanW

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I only do 5K changes on my 3.6L. I see zero reason to try and eek out every drop of oil life and to what end anyway--to have bragging rights? I have done my fair share of extended OCIs (15K+ miles), these days I would rather just know the engine is being maintained as well as it can be at a decent cost point.
Yep, I've settled in at 5k changes, too. I think it is a very safe OCI while still giving plenty of margin in case I can't get it done right away. I had good UOA's at 7500 to 8k but I feel good about 5k changes.
 

blnewt

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So true! I've had some engines with very bad reps that never showed me an issue. One was the Toyota slugde-o-matic 3.4 in my mid 90's 4 Runner. Mine never had the issue. I was running a top full synthetic oil that had much greater resistance to sludging, so when the looked at it as per the recall, they came back and said it not only was fine, but looked exceptionally good. I was doing the standard 3,000 mile oil changes back in those days. That vehicle then went to my Dad who ran it out to 200k or so before selling it. He continued the same maintenance practices and it never did have an issue and ran perfectly.
Same here, our 03 Runner was a gem!
 

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Plastic parts are the worst 'advancement' of the modern engine.
I have seen plastic cooling parts fail across all makes. It doesn't matter how good the engine is if a $20 plastic pipe fails.
No kidding! We had a 2010 Toyota Corolla S that had a plastic radiator in it. I was replacing the alternator in the car because it went out. Where the radiator cap is, there was an overflow tube going to the reservoir. I barely bumped it with an empty hand and it snapped off. I bumped it with such a minimal amount of pressure very similar to a light touch that it leads me to believe that it was already a degraded part that was soon to break on its own or that it was so poorly made that it never had any business being put into a vehicle. Anyway, as a result of that, I had to have the vehicle towed to a mechanic because I didn’t have the time or tools to repair the car because to replace the radiator, the front bumper and face must come off. The radiator was I think either $250.00 to $350.00, then a crap ton of Toyota coolant. Then while there I did preventative stuff too. New hoses, thermostat and so on and then the labor costs too. After all said and done, just for that repair was I think around $800.00 to $900.00 out the door. Which of course was in addition to the new alternator, battery and belts that I had also just paid for.
 

rcarbs

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3.6L engine completely unreliable
After 36000 miles, the engine started knocking
I had to replace an engine with the same engine type
At the cost of $ 8600 (Long Block without the all covers)
The service center does not take responsibility

Gray Oil.jpeg


WhatsApp Image 2021-07-12 at 14.49.41.jpeg


WhatsApp Image 2021-07-12 at 14.49.42 (1).jpeg


Old New Engine1.jpeg
Were you able to determine why it failed? Were you loosing coolant? Just wondering. Thanks.
 

Nissan

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Were you able to determine why it failed? Were you loosing coolant? Just wondering. Thanks.
Unfortunately, the service center does not know how to tell me what the problem is
They think it's because of the oil
But the strange thing is that they replaced a new engine and again found failures. (the new engine is knocking)
And I am again waiting for a new engine.
 

DanW

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Unfortunately, the service center does not know how to tell me what the problem is
They think it's because of the oil
But the strange thing is that they replaced a new engine and again found failures. (the new engine is knocking)
And I am again waiting for a new engine.
If that's number 2, I'd check the serial numbers on both engines and if produced in close proximity, it would be evidence of a factory defect. If not, then I'd look at the rest of the drive train. The odds are astronomical for the same problem twice with nobody else reporting it, so something external may be causing it.

What oil are you running? Also, are you purchasing fuel mostly from the same vendor? If so, I'd research any possible consumer complaints on that outlet or location. Have you run any fuel or oil additives?

Finally, have any other 3.6 owners in your area reporting similar problems?

Lots to consider when having 2 like failures back to back with an engine that has a stellar reliability and durability reputation in the global auto industry.

I hope your next one does much better for you.
 
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