New style VS old style PCV?

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Rayyy

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Apparently there is an old style PCV and a new style… Does anyone know which one is which?

I think the one with the small hole is the old style… but, can someone confirm?

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Rayyy

Rayyy

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For MY 2002, it originally came with the larger hole one with spring loaded valve ( rattles when you shake it). The "new" style is the one with the smaller hole, and has no internal spring/valve (no rattle).
Wow I thought it was the opposite… Rattler is the new type, no?

My 01 came with a non-rattler pin hole PCV, and the one I ordered was the spring loaded rattler.

Also, some of the videos I’ve seen on YT confirm this

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afpj

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Yours must have been replaced at some point. Gm changed to the fixed orifice ( non rattle type) pcv after complaints about oil consumption using the old style “rattle” spring loaded pcv. I am original owner so I’m confident that the rattle type is the older style. There’s a tsb on the fixed non rattle pcv to replace the rattle type. even later, gm switched to a different valve cover without a replaceable pcv.

a tsb is referenced in the following thread: https://www.chevyavalanchefanclub.c...sb-01-06-01-029b-excess-oil-consumption.3606/
 
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Rayyy

Rayyy

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Is there a way to replace the 03-06 PCV that comes with the valve cover?

I heard a pair of channel locks can be used to twist it out… Is this true?
 

Mudsport96

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Is there a way to replace the 03-06 PCV that comes with the valve cover?

I heard a pair of channel locks can be used to twist it out… Is this true?
Yes, it requires drilling and a little dremel work to get the right diameter for a grommet to fit. Then get a grommet and pcv for a 02 and prior setup.
Or go to the junkyard and just grab one from a 2002 or earlier vehicle. Ive done it both ways, and use them on my 06 Tahoe and Silverado. Just open up the drain holes in the baffle, they are TINY and plug with carbon. Then the oil goes through the pcv ( either style) and into the intake.
When i worked at the gm dealer we did this often and had zero returns for oil consumption or smoke.
 
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Rayyy

Rayyy

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Yes, it requires drilling and a little dremel work to get the right diameter for a grommet to fit. Then get a grommet and pcv for a 02 and prior setup.
Or go to the junkyard and just grab one from a 2002 or earlier vehicle. Ive done it both ways, and use them on my 06 Tahoe and Silverado. Just open up the drain holes in the baffle, they are TINY and plug with carbon. Then the oil goes through the pcv ( either style) and into the intake.
When i worked at the gm dealer we did this often and had zero returns for oil consumption or smoke.
Nice. Could you clarify which drain holes I would need to open up? Which baffle?

And if I clean these out, is there still a need to replace the PCV valve?

Also, do the 99-02 valve covers fit the 03-06 engines? Could I just install retrofit valve covers if I’m taking off the original ones to do the dremel work?
 
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Rayyy

Rayyy

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Indeed that thread is very informative.

So, it seems that the older valve covers with enlarged/slotted drain hole is the best of both worlds in the sense that it allows the oil to drain like the updated valve covers (Dorman part# 264-965), yet still has a replaceable PCV valve, ya?

Is there any benefit at all to just install the updated valve cover?
 

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