I’m being told my engine is bad

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Michigan

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2004 Tahoe z71 4x4

175k miles

Owned it 1.5 years

Got it with 149,500 miles

Has had a minor leak since I got it (was lied to about no leaks)

I used Mobil 1 5w-30 full synthetic high mileage and changed oil religiously every 5k miles along with Mobil 1 m107 oil filter

Always kept an eye on oil level and topped off if needed. Maybe a quart or slightly more every oil change

Engine ran very strong the whole time of owning

Without any signs it has developed a clunking sound on startup. This all happened in the past two days. Actually I had the oil changed yesterday and coincidentally it got way louder after the oil change. Before the oil change I barely noticed anything and I wasn’t even suspecting anything really.

On cold start it is very loud. Clinking/rattling noise. I was told by 2 shops it’s the bottom of the engine. Both shops were confident that that’s what it is. Then there is a junkyard across from my work and it took it to him for a third opinion and he says he’s certain it’s the flywheel that’s cracked. I called one of the shops back and told the guy I’m not going against what he’s saying but I asked him the possibility of it being the flywheel. He said that’s the first thing they checked, he said they removed the cover and all the bolts or screws where there? Not sure exactly.

I tried posting a video through YouTube but for some reason it won’t download. It just keeps saying processing. I tried posting a video directly on here and it says file too large. I’ll try to figure out how to get a video clip soon. I know not much you guys can go by without a video and still hard to diagnose by video as it is but would like to got some opinions

Also is there anything else I should have replaced if I have them do the swap. Both shops are suggesting to get a used engine to throw one in.

First shop say he located one with 113k miles from a guy that they do business with regularly. He want to charge 2,500. Not sure about warranty with him but he said he’ll go through the whole engine before installing and replace any manifold bolts of broken, plugs and what not

second shop said between 2,000 and 2,500 not warranty and can’t promise leaks or anything.
 

Kraig

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Clunking, knocking, rattling, or tapping? How’s your oil pressure now compared to what it was before this started?
 

Big Mama

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More info needed and have you been under it to tell exactly where it’s coming from and is it only at start up? As for engines check powertrain products they have a nationwide warranty. I wouldn’t go with any engine you can’t verify leaks or strength.
 
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Michigan

Michigan

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The video finally uploaded

Sorry not a great video. It was taken very quickly before work yesterday. I’ll try to get a better video and get the camera underneath the truck


Oil pressure has been fine. I think 40psi at idle and 60psi on the freeway.
 
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OP
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Michigan

Michigan

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More info needed and have you been under it to tell exactly where it’s coming from and is it only at start up? As for engines check powertrain products they have a nationwide warranty. I wouldn’t go with any engine you can’t verify leaks or strength.

I was underneath it at the shop yesterday. Both shops said it’s lower engine. Coming from the pan?

The noise is there at startup. Very loud on cold start then settles down. When the engine is warmed up and I start it up it’s not too noticeable. Not much noise if any at all when idling but then if I rev it up the noise gets louder.

While taking off at slow speeds you can hear it but above 30 the noise is completely gone
 

915_Tahoe

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one of my co-wokers says sounds like a flywheel. let me show this to a few technicians here at work and see what they think about it.
 
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Michigan

Michigan

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What’s the puddle?

Puddle is just rain
one of my co-wokers says sounds like a flywheel. let me show this to a few technicians here at work and see what they think about it.

Appreciate the input. I still plan on taking it to one more shop to get a third opinion.

I’m not very knowledgeable when it comes to engines but If the engine was bad wouldn’t the sound be consistent when idling? Instead it settles down and the noise goes away
 

Scottydoggs

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to rule out the flex, you take the three flexplate bolts to the torque converter, then fire it up. if its the flex the sound will be gone, if its still there its the engine.

does kinda sound like a flexplate. unless you broke a connecting rod, never heard a rod knock like that before, its more of a rhythmic banging sound.
 

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