Thread: WTF Flexplate broke/damaged Updated

I'm glad I haven't broken anything. Stock trans, stock wheel bearings, stock axles, stock flexplate...etc. Knock on wood.

Originally Posted by matt5112

Wheres brandon?

He bought his car then a month later the flex plate broke.

Car was bone stock.

He was the 7th post, Matt. Did you even read any of it? lol

Flexplates arent some sort of magical thing that need added stress on them to break.

They'll break in a bone stock car, that has taken enough abuse, or if there were imperfection in the metal when it was created.

2 front cover gaskets
machined oil pump cover
water pump gaskets
valve cover gaskets w/gromets
another set of LIM gaskets
head gaskets
front main seal
thermostat gasket
cam bolt
crank bolt
flex bolts
head studs
arp header bolts
double row timing chain
NEW OEM flexplate just cause they are cheap enough and I don't even remember where the 2 on my shelf came from

All that should cost a bit over $600, but will allow me to sell my RRs and L32 heads with 105#s and a set of cobra injectors I already swapped out and make back $4-500 maybe? Am I missing anything? Do I need lifters or are my stock l32 85K mile ones good? I don't plan on going over 6k rpm

Here's a funny thing. I beat the ever loving crap out of my car, enough to the point that I killed 5 built transmissions in one summer. (I'm not proud..gotta either laugh or cry..I'll take laughin and drinkin). Someone my flex never broke.

I did however have a redrilled one from when I had the trans done the first time (to use a 245mm converter) and the holes were a little egged. Upon doing my cam, the flex had been off and when I hand started the bolts, I was 180* off.

Yeah, I pulled the motor to rotate the flex.
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You can get away with not unhooking things 100% and not pulling things apart fully. I didn't take anything off the motor, I do when I pull one, but not to lift it for a min.

Originally Posted by BillBoost37

Here's a funny thing. I beat the ever loving crap out of my car, enough to the point that I killed 5 built transmissions in one summer.

HOW? DAMN!

Originally Posted by BillBoost37

You can get away with not unhooking things 100% and not pulling things apart fully. I didn't take anything off the motor, I do when I pull one, but not to lift it for a min.

I think I am gonna pull it soon and then build it with my IS2 heads and IS3 cam, keep the intercooler, and if I get enough back come tax time I may just buy a built trans and put it all back in together... If not I'm sure it won't be long.

So I pulled the motor sunday, took 3-4 hours taking most all accessories off and helping a guy from the car club change his wheel bearing at the same time. I don't see any cracks whatsoever on this thing but its for sure not flat when laid it on the two good ones I have. But its only like .032 off at the farthest point. It did have a rub mark on the back all the way around but for the life of me I can't tell what it was actually rubbing on the motor...

hmm. just from the pics i can't really see anything just obviously cracked.

but for reference, here is mine. it was actually cracked in two places. just look for those hairline cracks.

I'm gonna wire wheel it next time I'm out in the garage and check closer but there's none that can be seen with a flashlight and my face an inch away from it. Just that little tiny bit of bend in it... May have happened when the junkyard pulled it, during shipping, during install, when I swapped the trans... Who knows, just picked a really really odd time to make itself evident. I'm gonna bolt it back on and see if the starter can spin it fast enough on the stand to make it wobble or hit a bolthead on the motor or something

if you were to tap the flywheel with a hammer, wouldn't it have a different tone if it were cracked? being that you have a known good one to test out side by side.

i dont know this for a fact, but it may just sound different.

Gonna pry on it side to side in the vise too and see what I see... I'll try that hammer/tone thing too and see.

if you were to tap the flywheel with a hammer, wouldn't it have a different tone if it were cracked? being that you have a known good one to test out side by side.

i dont know this for a fact, but it may just sound different.

So after cleaning it with a wire wheel on the angle grinder I still saw no cracks whatsoever. Tried hitting it with a hammer and listen for tonal changes and obvious now after doing it the part with the cutouts sounds different than the rest and that's where my cracks would be... Just going to retourque the bolts on the back cover and see if any move too much as in one may have backed out. But on the brighter side I ordered my parts, should be here by the end of the week. I broke the cam magnet pickup somehow and need to find another in short notice if I want to have this engine back in before it gets too cold to work outside if anyone has one??? Here's my parts list, anyone care to add??? And do we still have to machine the crank gear on the double timing sets to get them to align or has this issue been fixed? How beneficial would it be to degree the cam since I have the option to?

Seeing that mark, makes me think rear cover bolt for sure.

Little late, but a bit ago I disassembled one of my transmissions to check what parts I needed for a rebuild. I inspected the differential and other parts to see what needed to be replaced. I put the differential with the output shaft on a tray under the car in the garage. About 6 months later (without moving it at all). Still without moving it, I looked at it and it had an obvious crack in the casing of the differential. This was over winter so it appears it was weak and then from the expand and contraction, cause sometimes I would run a heater in the garage, it developed a crack. Car was supposed to have about 300 whp at that time.

Originally Posted by BillBoost37

Seeing that mark, makes me think rear cover bolt for sure.

I thought for sure too but I see no rub marks on ANY surface anywhere on the back of the motor and with it mounted it looks to be at least an 1/8" away at all times. Here's how bad it looks in rotation though... I had 4 of the bolts back in kinda snug is all but you can sure see it

Bent flex - YouTube

Originally Posted by RegalGS98s

Little late, but a bit ago I disassembled one of my transmissions to check what parts I needed for a rebuild. I inspected the differential and other parts to see what needed to be replaced. I put the differential with the output shaft on a tray under the car in the garage. About 6 months later (without moving it at all). Still without moving it, I looked at it and it had an obvious crack in the casing of the differential. This was over winter so it appears it was weak and then from the expand and contraction, cause sometimes I would run a heater in the garage, it developed a crack. Car was supposed to have about 300 whp at that time.

It would be different to be able to see a crack. At least then I would have the reason why it just all of a sudden started this. I find it hard to believe it's been bent for however longs its been bent and hasn't shown any signs til now. The last time I had it apart was for the trans and that was this time last year I think, and its got maybe 3k miles on it since then. Ended up being a great excuse to install my heads and cam that were just sitting in a box though

But you know that something rubbed...and now it's bugging you and I both.

Have you slid the TC off the trans yet? I'd think that if the flex was warped...it would have straightened over a year being bolted to the TC.

Originally Posted by BillBoost37

But you know that something rubbed...and now it's bugging you and I both.

Even with it running on the car though and my flashlight between it and the motor I still didn't see anything hit... Nothing really lines up just right with that rub mark around the back either...

Originally Posted by BillBoost37

Have you slid the TC off the trans yet? I'd think that if the flex was warped...it would have straightened over a year being bolted to the TC.

No, I haven't really even looked at it cept to bolt a strip of wood to the case to keep it from falling out when I rolled it around the drive the other day. I'll be pulling it now to check it best I can for straightness though now that you mention it. That's the other thing I don't get, if it was bent, its been bent for a year and running fine. The TC to flex bolts all felt liked they were torqued the same when I removed them but I used my impact on the flex to crank bolts and they seemed to come off pretty easy(none were backed out though)... Before it occurred to me to use a wrench and really check tightness I was done. Damned speedy impacts...