Oil prime

2004LB7

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Dec 15, 2010
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Those look like fatigue cracks due to constant flexing. Id make sure the transmission was seated to the engine correctly and flush. Also no debris or anything stuck between the converter and flex plate or transmission and engine. Just a small amount of continuous flex due to a misalignment can do that
 
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ikeG

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Those look like fatigue cracks due to constant flexing. Id make sure the transmission was seated to the engine correctly and flush. Also no debris or anything stuck between the converter and flex plate or transmission and engine. Just a small amount of continuous flex due to a misalignment can do that
I didn't see any issues taking it apart. Not sure what to think

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TheBac

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Apr 19, 2008
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I can remember seeing that on higher-hp trucks in the past, but not stock. Did anything else seem odd when you took it apart again?

EDIT: you answered that earlier.

Must've just been fatigue from use.
 

ikeG

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Washer
b6da8d69ad71dbe6af194c1d259be618.jpg


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Chevy1925

don't know sh!t about IFS
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Any idea where the heat marks on the flex plate came from? Theres two spots that look like they got hit with a torch. Could have harden there, cracks started and bye bye
 

ikeG

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It does look like that but that could be from the friction while running it. He actually drove like this for a while, towing snowmobiles. An employee did this job from start to finish in Aug, he's quit Dec 31. But even if he took a torch to the flywheel bolt heads I don't think it gets spots like that.
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JoshH

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I think James is on the right track. I bet your former mechanic heated the bolts with a torch and got a little wild with the flame.