I’m being told my engine is bad

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tedv

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You're going to say that I'm crazy, but shortly after I had a rear main seal on my 2000 Suburban repaired, I developed a knock that sounded like a loose rod. Actually, I found one of the crossmember bolts' was loose and rattling. It was easy to check and repair, but it took me a month of running to shops and finally I crawled under and smacked everything I could with a mallet until I found it. Check and make sure the nuts on that crossmember are tight to the bolts ... think there are four of them.
 
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TahoeFL2017

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Thanks for that swathdiver

And thanks I will try the what you guys suggest with the catalytic converters

So I parked the truck Wednesday night around 1 am and have not drove since so it sat for about a day and a half and this was a cold start Friday morning. Again sorry it was just a quick video before leaving to work in a different vehicle so I rushed the video

Oddly enough this time when revving up the engine it did not really make the noise but on Wednesday when I showed it to a few people the noise was there every time I revved the engine. I may have to wait till Tuesday till I get it into a shop.



I had a old chevy motor that threw a rod, after 3 months of driving it knocking, I'm thinking its the flex plate or cats, does not sound like bottom end. Old beater trade-in that I bought to give to my brother for $150 bucks, temp transportation , we knew it would blow up eventually.

My rod knock sounded loud, and speeded up and slowed down exactly equal with revving the motor. Sounds more like something came loose and is bouncing around in there.
 

tedv

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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.
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.
Go read my post about checking crossmember nuts and bolts to make sure they're tight. My 2000 Suburban made the same sound as yours is making and one of the crossmember bolts was loose.
 

Scottydoggs

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just so we all know. a rod knock will never just stop and start again. driven long enough its not a knock any more its a bang, hard bang you can feel. the more rpm, the more banging. i drove my 77 gmc with a rod knock for months, till i scored a used engine, it was so loud. i mean loud, cant even talk over it. so id do a lot of getting it up to speed and toss it in neutral and coast as long as i could. i was really hoping the rod would give out and blow through the pan or block, but she held up.
 
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Thanks again for all the help.

Little update but problem not solved yet

I haven’t drove the truck since last Wednesday (exactly a week)

So this morning I started it up, no noise at all

I drove it to a nearby gas station that has a garage there, about a 4 mile distance from my house

Made no noise at all on that trip even when arriving so I thought great this might be hard for them to check for the noise when it’s not there

I planned to have the guy to lift it and check for the crossmember bolts (I know I should be able to do this myself) also I let him listen to the video and he agrees that more than likely it’s the flywheel (flexplate)

Anyways he said to just drop it off one day.

So I left and I work about 24 miles from there, first intersection I came across I made a sharp right turn and I heard the noise for just a moment

Now that I think about it I forgot to note before any of this really loud noticeable noise I would hear hear this noise slightly when making a big turn I.E going on a freeway ramp I started to notice the same noise

Does this indicate anything or help narrow anything down?

Also for the rest of my 24 mile trip to work I did not hear any noises even when coming to stops and parking.
 

swathdiver

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Thanks again for all the help.

Little update but problem not solved yet

I haven’t drove the truck since last Wednesday (exactly a week)

So this morning I started it up, no noise at all

I drove it to a nearby gas station that has a garage there, about a 4 mile distance from my house

Made no noise at all on that trip even when arriving so I thought great this might be hard for them to check for the noise when it’s not there

I planned to have the guy to lift it and check for the crossmember bolts (I know I should be able to do this myself) also I let him listen to the video and he agrees that more than likely it’s the flywheel (flexplate)

Anyways he said to just drop it off one day.

So I left and I work about 24 miles from there, first intersection I came across I made a sharp right turn and I heard the noise for just a moment

Now that I think about it I forgot to note before any of this really loud noticeable noise I would hear hear this noise slightly when making a big turn I.E going on a freeway ramp I started to notice the same noise

Does this indicate anything or help narrow anything down?

Also for the rest of my 24 mile trip to work I did not hear any noises even when coming to stops and parking.

Rule out those cats.
 

PG01

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Thanks again for all the help.

Little update but problem not solved yet

I haven’t drove the truck since last Wednesday (exactly a week)

So this morning I started it up, no noise at all

I drove it to a nearby gas station that has a garage there, about a 4 mile distance from my house

Made no noise at all on that trip even when arriving so I thought great this might be hard for them to check for the noise when it’s not there

I planned to have the guy to lift it and check for the crossmember bolts (I know I should be able to do this myself) also I let him listen to the video and he agrees that more than likely it’s the flywheel (flexplate)

Anyways he said to just drop it off one day.

So I left and I work about 24 miles from there, first intersection I came across I made a sharp right turn and I heard the noise for just a moment

Now that I think about it I forgot to note before any of this really loud noticeable noise I would hear hear this noise slightly when making a big turn I.E going on a freeway ramp I started to notice the same noise

Does this indicate anything or help narrow anything down?

Also for the rest of my 24 mile trip to work I did not hear any noises even when coming to stops and parking.
Still betting on pickup tube in pan
 

Doubeleive

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I would very cautious driving it until you figure out the problem or just not drive it I would be leaning more towards that flexplate it could just happen to be catching on at the moment, you could go buy one of the those cheap inspection cameras and stick it up inside anywhere you can fit it in to check that flexplate
 

Big Mama

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Yeah I was hoping the cat had stuck combs but they would have come loose on that drive. I’m back on the flex plate wagon. As Wes stated you can get a cheap inspection camera and end the guesswork.
 

Doubeleive

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What could happen if the flexplate breaks? Catastrophic damage?
I can only imagine, a metal saw type thing spinning at 2500rpm and deciding i'm going to just go this way...or maybe just fling myself around inside and screw everything up, couldn't be good, I think that why race cars have to have guards installed in case that thing decides to cut loose.
 

Big Mama

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And then some. It’s heavy steel disc spinning fast and coming apart in pieces that go through just about anything including your legs.
 

Tonyrodz

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I can only imagine, a metal saw type thing spinning at 2500rpm and deciding i'm going to just go this way...or maybe just fling myself around inside and screw everything up, couldn't be good, I think that why race cars have to have guards installed in case that thing decides to cut loose.
And then some. It’s heavy steel disc spinning fast and coming apart in pieces that go through just about anything including your legs.
That would suck for sure. I think I'm having the same issue with my van--similar symptoms.
 

Jeff Groves

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1984 I had a Camaro I built. Since I was running a triple stage Nitrous system I added a safety blanket to the 700R4 I had built myself.
Flex plate went grenade so glad I had that!
 

pwol1962

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I had one of the bolts come loose that secures the torque converter to the flywheel on my 2001 Yukon several years ago. The bolt was being knocked around by the rotation of the flywheel/torque converter and it sounded exactly like your posted audio recording
 

SRQYukon

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I'm not weighing in on what it might be except to say that when my cat failed at 79K it did not sound like that. I actually thought it was a loose heat shield on the cat. Sounded like sheet metal rattling. I was really surprised when the tech at the dealer told me that the guts had come loose and just 1000 miles before my emissions warranty expired. And mine didn't make any discernible sound above 1200 rpm. BTW, I gotta love the self-confidence you all have, but everyone can't be right. Or at least for his sake I hope it's not "all of the above".
 
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BG1988

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My truck sounded just like that when the catylitic converter failed. The ceramic internals were rattling around inside the cat. Try hitting the cats with a rubber mallet and listen for a rattling sound.

Sent from my SAMSUNG-SM-G930A using Tapatalk
then he would have 420 stoner code
 

jeffsyukon

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then he would have 420 stoner code
Mine didn't smell. No 420 code. Just noisy and turned out to be the catylitic converter. Sounded like rocks banging around in the exhaust pipe. The noise was intermittent and very loud at times.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
OP
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Ok so just got the call from shop I dropped the truck off to and the guy said he’s 100 percent certain it’s a bad cat.

What are my options here? He said about 800 to replace the whole h pipe with the 2 catalytic converters which I thought was way high.

I read that it’s not illegal to remove a non functioning cat. I read that only if you remove a fully functional cat that it’s illegal. In my state we don’t have inspection

The guy did tell me that gas mileage and performance will suffer if we straight pipe it. Thoughts?

also now that we know it’s a bad cat, is it ok to drive like that till I get it fixed? I’m assuming it is ok

Not sure where the guy is coming up with 800 but so far from a quick search I found this http://vi.raptor.ebaydesc.com/ws/eB...ategory=33629&pm=1&ds=0&t=1559682870000&ver=0

Not sure if that is cheap quality but it shouldn’t be anymore than a 100.00 to install I’m guessing as it’s a direct bolt on.
 
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