GM LZ0 bypass spec?

[UNC196]

GM LZ0 has an engine mounted bypass valve and the factory filter has no bypass valve for that reason.

Does anyone know the psi at which the engine mounted bypass opens?


If using an aftermarket filter with a lower bypass psi rating, wouldn’t it bypass unfiltered oil more frequently?


It seems logical, that you would need to know the spec for the engine mounted bypass and stay above it?

 

[SubieRubyRoo]

Pump bypasses and filter bypasses work on different principles. They’re not comparable in function or rating.

 

[mdc09]

I've tried looking this up before but have never found any psi ratings.

 

[mdc09]

Pump bypasses and filter bypasses work on different principles. They’re not comparable in function or rating.

These engines has the filter bypass mounted where you screw the filter on.

 

[ZeeOSix]

GM LZ0 has an engine mounted bypass valve and the factory filter has no bypass valve for that reason.

Does anyone know the psi at which the engine mounted bypass opens?

GM LS engines also have the oil filter bypass valve in the engine, and those are set to 11-12 PSI based on someone actually measuring the acting area and the force to crack it open. I'd think GM might use that some setting on similar engines. Most aftermarket filters will have a bypass valve set higher than that, so if you're going to use a filter with a bypass valve, make sure its bypass valve setting is say 16 PSI or more.

 

[MurkyAsparagus]

LZ0 uses a PF66 like a lot of other GM vehicles. My ‘23 blazer runs the same. Around a year ago I asked O’Reillys what the bypass PSI was on the MSL10351 (cross referenced PF66) and this was their response: