Lq4 Flexplate
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Lq4 Flexplate I’ve recently discovered that my flex plate has destroyed itself, converter and transmission on 6.0/4l80. I was running a tci Flexplate so I’m not looking to go back to them. I have a 2001 6.0 lq4 and 2001 4l80. the motor has been fully rebuilt with power adding components. making about 500 to the crank. I will be rebuilding the transmission to hold about 800 and installing a 2800-3000 stall converter. Any recommendations? Thanks for any help.
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^^^ This ^^^
A flex plate has no mechanism available to it, to "destroy itself" with; let alone to destroy anything else. It can BE DESTROYED by various things, butt not "destroy itself".
There's no way a motor with that little power should be able to damage a flex plate. You need to figure out what REALLY happened, lest it just immediately happen again to another one.
A flex plate has no mechanism available to it, to "destroy itself" with; let alone to destroy anything else. It can BE DESTROYED by various things, butt not "destroy itself".
There's no way a motor with that little power should be able to damage a flex plate. You need to figure out what REALLY happened, lest it just immediately happen again to another one.
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@RB04Av and @Old Buzzard I'm curious here.
What would cause damage to a flexplate? 🤔🤷
Thrust bearings out of spec maybe? Wouldn't that also cause damage to the transmission pump (automatic transmission)?
What would cause damage to a flexplate? 🤔🤷
Thrust bearings out of spec maybe? Wouldn't that also cause damage to the transmission pump (automatic transmission)?
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From: Bostwick, GA.
"I’ve recently discovered that my flex plate has destroyed itself, converter and transmission on 6.0/4l80".
Your lack of detail, pics, etc, in your description makes a reply pretty much impossible.
?1 Are you saying the converter and the trans are damaged?
Further details and pics absolutely necessary.
Your lack of detail, pics, etc, in your description makes a reply pretty much impossible.
?1 Are you saying the converter and the trans are damaged?
Further details and pics absolutely necessary.
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Zackly.
This post is altogether too vague to even make sense out of, let alone diagnose the problem. Details are required. Photos might be helpful butt maybe not necessary.
Main things I can think of that would damage a flex plate are: improper assembly, like not tightening the bolts; and a defective starter. Beyond that, we start getting into speculating about alien abduction and quantum entanglement as potential causes. Thrust bearings can't really do that, at least not at a level where the post would be ANYTHING about "flex plate", instead of "my engine is COMPLETELY destroyed and making loud banging noises, and there's about a pound of metal shavings in the oil".
This post is altogether too vague to even make sense out of, let alone diagnose the problem. Details are required. Photos might be helpful butt maybe not necessary.
Main things I can think of that would damage a flex plate are: improper assembly, like not tightening the bolts; and a defective starter. Beyond that, we start getting into speculating about alien abduction and quantum entanglement as potential causes. Thrust bearings can't really do that, at least not at a level where the post would be ANYTHING about "flex plate", instead of "my engine is COMPLETELY destroyed and making loud banging noises, and there's about a pound of metal shavings in the oil".
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I have replaced many flex plates on different vehicles from civics to dodge caravans due to them breaking. Sometimes they just crack and then some times they break in pieces...
Obviously improper install, setup, abuse or power levels will cause failures but that isn't always the case.
Having said that... the stock one should be just fine..
Was a lq4 from 2001 still a "long crank" or did that end in 2000?
Obviously improper install, setup, abuse or power levels will cause failures but that isn't always the case.
Having said that... the stock one should be just fine..
Was a lq4 from 2001 still a "long crank" or did that end in 2000?
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LS from 99 into 05 longer crank shaft I'm sorry if this message is wrong I'm taking the ls out of my 99 which has a longer crankshaft and putting it in my 05 2500 which had a spacer on the back of it when we tried to bolt the transmission up there was a gap and it was tight at the top and gapped at the bottom I was told my crankshaft is longer in that motor can I get a shorter torque converter or what can I do I've already put the motor in a couple times I don't have the money to buy a new motor or transmission me and my buddy are doing it ourselves it's been 5 days and I need my truck for work
I'm sorry if this message is wrong I'm taking the ls out of my 99 which has a longer crankshaft and putting it in my 05 2500 which had a spacer on the back of it when we tried to bolt the transmission up there was a gap and it was tight at the top and gapped at the bottom I was told my crankshaft is longer in that motor can I get a shorter torque converter or what can I do I've already put the motor in a couple times I don't have the money to buy a new motor or transmission me and my buddy are doing it ourselves it's been 5 days and I need my truck for work
Literally is that simple.
Simple research 5 days ago could have given you that answer..
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Flex plates break. We all get that.
They don't "destroy" converters, transmissions, etc. when they do. They just make abuncha noyzzzze for awhile until they completely let go, and then the car has no drive until you replace it.
There's more to the original post, the diversion notwithstanding, than he wrote. We're waiting for The Real Deal and of course The Rest Of The Story to help that d00d out.
They don't "destroy" converters, transmissions, etc. when they do. They just make abuncha noyzzzze for awhile until they completely let go, and then the car has no drive until you replace it.
There's more to the original post, the diversion notwithstanding, than he wrote. We're waiting for The Real Deal and of course The Rest Of The Story to help that d00d out.
Transmission could have wasted a Planet, sent chunks into the Convertor and wadded the Convertor, I've seen that. If it became unbalanced it possibly could crack the Flexplate but that's a longshot.
This part here "the motor has been fully rebuilt with power adding components" is what lost me, it's been 5 days since the first post clearly they are concerned with it.
This part here "the motor has been fully rebuilt with power adding components" is what lost me, it's been 5 days since the first post clearly they are concerned with it.
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break the flex plate. It cracked around the bolt holes.
Thing is, a flex plate cracking around the bolt holes DOES NOT "has destroyed itself, converter and transmission". Unless it literally exploded, such as from excessive RPMs (which is why they make you have a scatter shield of some sort below a certain ET); which I've "heard" of, butt never experienced even 3rd or 4th hand that I could verify, and it doesn't seem at all likely in a LQ4 truck setup. So whether a flex plate can break or not, ISN'T the concern at hand. All the rest of that, IS.
Maybe the OP will come back and fess up to whatever REALLY happened. Maybe he was just looking for a pity party or some TCI-bashing or some other random thing, besides ... not sure what. Maybe SOMETHING ELSE happened that wiped out ALL of it, and the flex plate was just one of the victims, not the perp at all. Maybe we'll find out.
Last edited by RB04Av; Nov 21, 2024 at 02:23 PM.