Flexplate Question

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paulutions

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2000 Tahoe Z71: I'm replacing the flexplate and the mounting bolts. Factory bolts had no thread locker, no lock washer. Autozone bolts look a little different but have same number of threads, lock washers and were like $10 for all 6. Dealership has factory bolts for $6 a piece. My question is: are the aftermarket with lock washers better? Do I take the lock washers off? Do I go with factory? Do I use thread locker on either? I know it may seem like splitting hairs but these flexplates seem to be a problem for a reason that, apparently, the factory didn't sort out. I had the same issue with an 85 suburban where the flexplate bolts loosened up just enough to wobble the plate until it broke and I don't understand why GM never put lock washers or thread locker on these bolts from the factory.
 

swathdiver

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2000 Tahoe Z71: I'm replacing the flexplate and the mounting bolts. Factory bolts had no thread locker, no lock washer. Autozone bolts look a little different but have same number of threads, lock washers and were like $10 for all 6. Dealership has factory bolts for $6 a piece. My question is: are the aftermarket with lock washers better? Do I take the lock washers off? Do I go with factory? Do I use thread locker on either? I know it may seem like splitting hairs but these flexplates seem to be a problem for a reason that, apparently, the factory didn't sort out. I had the same issue with an 85 suburban where the flexplate bolts loosened up just enough to wobble the plate until it broke and I don't understand why GM never put lock washers or thread locker on these bolts from the factory.
I've only had issues with the bolts getting loose because they were not torqued properly, this was always after the engine or transmission had been out of the vehicle, not from the factory but I suppose it could happen.

Just looking the bolts up for mine, thinking they would be the same for yours and am seeing the blue thread sealer on them, $12.60 each, 11546840. I would not have a problem using an "aftermarket" bolt as long as the specs are the same, in five minutes of googling I could not determine what grade they are.
 

Fless

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Just looking the bolts up for mine, thinking they would be the same for yours and am seeing the blue thread sealer on them, $12.60 each, 11546840. I would not have a problem using an "aftermarket" bolt as long as the specs are the same, in five minutes of googling I could not determine what grade they are.

I've seen two places that spec them at Grade 8.8. Here's an aftermarket bolt at Rock Auto:

1682213106061.png
 
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paulutions

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Just looking the bolts up for mine, thinking they would be the same for yours and am seeing the blue thread sealer on them, $12.60 each, 11546840. I would not have a problem using an "aftermarket" bolt as long as the specs are the same, in five minutes of googling I could not determine what grade they are.
Thanks. Those are the torque converter bolts and I am talking about the flexplate to crank bolts. But, after talking to a GM mechanic it seems that the thing to do is to buy the new OEM bolts without the lock washers and use some blue thread locker, so that is what I intended to do. However, the damn new flexplate doesn't quite fit over the end of the crankshaft and when I talked to the GM guy about that he said that its not uncommon with the made in Mexico aftermarket ones and to just return it and get another. So, back to the auto part store......
 

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