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Discussion Starter · #1 ·
I am replacing the passenger-side head gasket on my 2008 Sierra 5.3L. After installing the gasket/head and TTYing, I realized I likely need to clean my valves and replace the valve stem seals. While I know I would need new head bolts, will the head gasket need to be replaced also? The truck has not been started since installing the new head gasket and I wouldn't think there would be a problem reusing it. Just wanted to check here in case the head gasket seal is compromised in some way after torquing down the head.

Thanks!
 

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1999 Silverado ECSB 6.0
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You'll be fine go ahead and reuse them
 

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I would never reuse a head gasket. Ever.

They are cheap, and it needs to come off anyway. They are meant to be torqued once and that's it. They crush and that's what seals the head to the block. So removing it and then trying to re clamp it and expect it to seal is a big mistake.
 

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He never cranked it. He'll be fine. If the engine had turned on then yeah I would so no but in this scenario he will be fine.

He is using a new head gasket not reusing his old one
 

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Once the head is torqued down, the gasket is done. It is already crushed and sealed to the head and the block.

You can not remove the clamp load, then reuse that gasket. Doesn't matter if the engine was ran or not, that makes zero difference. Once they are crushed, that's it. There is not a head gasket out there that can be reused that I know of, be it the multi layer steel, or the graphite type gaskets.
 

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I wouldn’t reuse one. They are too cheap, and it is too much effort to get to it if there is a problem. I would probably leave he head on and just replace the seals in situ. If it were mine I wouldn’t put the heads back on without a valve job and true them up.
 

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2010 Silverado LS WT RCSB 4.3 v6
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I totally agree with the above. Gaskets are too cheap for me to think about reusing one it leaking or coolant getting in the cylinders. Besides is the risk worth having to tear it down again and install a new gasket? Buy a new gasket if you are removing the head again.
 

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How do you think shops check piston to valve clearance? They aren't going to have new head gaskets to put on every single time.

Are these MLS gaskets? If they are not then my opinion would change and I would say get a new one but MLS will be alright. Heat is what kills gaskets more than compression
 

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Here because I was curious I called fel-pro. I wish I could give a transcript but they say as long as the gasket is not torn or messed up you can reuse them since it has not been through a heat cycle.
 

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That's sketchy as hell that a company said that lol.

Every single OEM that I've worked for/on, the head gaskets are a one shot proposition. Same for TTY bolts. Not just head gaskets either. Practically any gasket that is steel, fiber, or composite. Always the same, remove gasket and discard.

But I guess it's up to the OP. If they feel comfortable knowing they may need to pull the head again if the gasket doesn't seal, because they didn't want to spend the $40 for a new one, then go for it haha.
 

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Who else should I call? I'm bored at work lmao

The TTY bolts yeah I would probably go buy some ARP and call it a day. Those I don't think I would reuse since they physically are not made to be reused. Basically you break them once they get torqued down.
 

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Don't matter to me haha. I've never been able to successfully remove an MLS gasket once torqued without it sticking to the block, head, or both and ripping the coating off anyway so that alone lands the gasket in the trash can lol.

But you can physically see the difference in a gasket from brand new, and one that's been torqued down. Noticeably flatter and the sealing "bosses" are crushed.

I'm sure people reuse them and get away with it. Just you'd never catch me doing that. Especially with how dirt cheap and easily obtainable they are for these motors.
 

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Every single OEM that I've worked for/on, the head gaskets are a one shot proposition.
Yep, Deere wants it replaced if you set the head on and have to pull it back off for some reason even if it hasn't been torqued.

Sent from my SM-N981U1 using Tapatalk
 

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Discussion Starter · #14 ·
Thanks guys! I have decided to simply replace the seals with the head attached. Not worth the slight chance of screwing something up. I appreciate the feedback.
 
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