Are all GM crankshafts the same

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Jul 2, 2009 | 03:54 PM

racecar

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Are all GM crankshafts the same

I'm looking at buying a used GM LS crankshaft 3.622 stroke with a 24X timing wheel.
Are all the 3.622 stroke cranks the same? I don't know if I am getting an LS1 or an LS6, is there a difference in metals or design, or anything???

Jul 2, 2009 | 04:33 PM

LS1Formulation

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I just bought an LS6 crank from Katech. It's functionally identical to an LS1 crank. What I don't know is if GM used a different casting for 5.3 or 6.0 truck engines due to the piston weight being different in those engines. Maybe someone with a little more knowledge can chime in here.

Jul 3, 2009 | 01:29 AM

racecar

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All LS1 or LS6 cranks should be the same? Maybe the truck engines have more counterweight.

Jul 3, 2009 | 01:48 AM

blackLS1m6

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They are the same but the truck cranks had a wider rear seal surface.

Jul 3, 2009 | 09:38 AM

got-a-ls1

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From: earth

truck cranks are also not drilled like the ls1 cranks in the journals, if memory serves correctly... which means they are heavier, but not necessarily stronger.

Last edited by got-a-ls1; Jul 4, 2009 at 04:57 PM.

Jul 4, 2009 | 01:13 PM

1FastBrick

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From: JunkYard

Cranckshafts with the 12552216 casting number = Same crankshafts but machined differently for each application. All interchangeable just be sure to have it ballanced for your application.

https://ls1tech.com/forums/11028189-post4.html

https://ls1tech.com/forums/generatio...lq9-crank.html