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Old 05-21-2007, 01:06 PM   #1
crm318
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cracked flywheel symtoms

i think that i might have a cracked flywheel. lately i have been hearing this clicking in my engine compartment only when i give it gas. i have looked at everything and nothing was out of order. no loose bolts or anything making contact with anything. then the next time i heard it. i got down by the flywheel and torque converter and that is where the sound is coming from. how much does a new converter cost? if i found one in a parts yard, would that be a bad idea?
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Old 05-21-2007, 01:12 PM   #2
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Re: cracked flywheel symtoms

Do you think it's the converter? I think if you're hearing the noise from there it's the flywheel. I bought my new one for $35 at the local parts house. I'm not sure what a converter costs though.
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Old 05-21-2007, 01:19 PM   #3
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Re: cracked flywheel symtoms

a cracked flywheel sound tinney. crawl under the truck and use a flash light to look around the flywheel bolts and the holes that are punched in the flywheel
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Old 05-21-2007, 01:41 PM   #4
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Re: cracked flywheel symtoms

If you are going to go to the trouble off buying a new flexplate for your engine. Purchase one that is SFI rated and heavy duty. I went through a couple flexplates on one truck until I got smart and purchased a heavier plate. The torque convertor ballooning is what cracks them, That is by design, so it is not bad.
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Old 05-21-2007, 02:07 PM   #5
crm318
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Re: cracked flywheel symtoms

what is ballooning? the sound is a high pitch clanking. what tooth flywheel will i need?
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Chevrolet red and white
357ci, Vortec heads,
GM Performance high rise intake,
Comp 268H .454/.454 218/218 110 LSA
Quadrajet carb, Flowtech headers, 2.25 40 series
HEI, Curve kit, TH 350, 3.07 gears
275/60/15s on 15x8 rallies

Last edited by crm318; 05-21-2007 at 02:08 PM.
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Old 05-21-2007, 02:20 PM   #6
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Re: cracked flywheel symtoms

Should be a 168 tooth. I agree go SFI approved. I havechanged out to stock one in mine before I went SFI
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Old 05-21-2007, 03:00 PM   #7
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Re: cracked flywheel symtoms

I had my transmission out to relpace the pump seal and noticed the flexplate was cracked. Very common for these engines. Was not making any noise at the time but it had just started to crack.
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Old 05-21-2007, 04:05 PM   #8
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Re: cracked flywheel symtoms

As you apply different RPMs and change pressure on the tranny the torque convertor balloons out and changes sizes and thicknesses, that is ballloning on the convertor. That causes the flexplate to crack and make those funny chirping noises from under your truck. So to fight back get a thicker and heavier duty flex plate. (note the name)
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Old 05-21-2007, 04:16 PM   #9
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Re: cracked flywheel symtoms

We bought my Sons truck cheap becase the guy said it had a rod knox. It was just a cracked flywheel, it sounded bad on acceleration
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