Rattle in oil pan below 700rpms

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usar17

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I bought a new flexplate and bolts anyway since its apart. Putting it back together today

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usar17

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All bolted back up. No more noise. Damn flexplate bolts

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CSFJ

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All bolted back up. No more noise. Damn flexplate bolts

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Did you happen to loctite them this time?
 

usar17

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Yes i did! And had a nice talk with my friend that assembled them last

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CSFJ

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Yes i did! And had a nice talk with my friend that assembled them last

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Lol. Reason I asked about the loctite, back when I was into jeeps, a buddy had dropped the trans on his, and ran into the same issue. Turns out, the 4 cylinder models required loctite, but not the six cyl. Guess they figured the 4 rattled more.
 

usar17

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New issue I found. After road testing with the new flywheel I have a shake while the torque converters locked. What would have caused this. What did I put back on wrong

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Cuba

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Trans bolts torqued to spec? Everything lined up ok? Driveshaft misaligned somehow? You didn't have to mess with too much to replace the plate...
or trans mount not tight?
 

usar17

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No it was a fairly easy swap out. Nothing is shaking in idle. Its only when the torque convert locks up

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Cuba

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Yeah, that registered after I posted. I can't think of anything in particular with those exact symptoms. I just started throwing out ideas. The only other thing that comes to mind is the flexplate & its weights. But I'd think you'd feel it in the lower RPM too.

Or the torque converter itself... But you've had it up to lockup before, right? Never any issues until this flexplate issue?
 
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usar17

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Any thoughts that i somehow have tcc shudder now? No clue why

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Where did the flexplate come from? I'd guess it is not balanced quite right and it becomes evident when the converter is locked. Lower rpm and higher load might be creating the perfect storm.
 

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If the flex plate was out of balance, I believe that You would have vibration in park or neutral when the engine is revved.
No idea other wise except if the clutch in the TC is slipping.
 

usar17

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Was a cheap autozone pioneer flexplate. But i swapped a good one in and still have the issue

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Cuba

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Maybe look at some other components, such as the carrier bearing for driveshaft (if applicable), trans mount, etc. It is very possible that something else just happened to go bad at the same time. Could it be possible that it just feels like it's happening at lockup and not directly related to speed? Not that I'm doubting you, just stranger things have happened.

Like for example, unbalanced tires can have a vibration "sweetspot" at 40 -45mph, where it's most pronounced. You may hardly feel it under or over the "sweetspot" mph.

Just to be clear, you're on the 3rd flexplate then? The 1st original with the rattle, the 2nd where the rattle was corrected, and now a 3rd to replace the AZ cheapy?
 

usar17

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Yes 3rd

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