L29 Oil Cooler line routing clarification

[Philip Parker]

Hi everyone - been sorting through this info on my rebuild and I am finding conflicting information.

This is how I understand it:

The oil cooler lines on a Gen VI come from the oil pan rail next to the oil filter. They are tapped fittings into the gallery with quick connects on them. The REARMOST fitting with the plastic basket sends oil to the cooler (in my case integrated into the radiator) to the lower port on the radiator. The FRONTMOST fitting returns the oil from the top fitting on the cooler to the engine. The lines are different lengths and can only be attached to the integrated cooler in one way.

Is this correct?

The new line that SENDS the oil to the cooler that I have says "In" on it. The other says "Out". this means into the cooler and out of the cooler. Scoggin Dickey has a part to plumb it all with AN but their diagram is all funky with the Oil Filter pad on the wrong side of the oil pan rail:

https://sdparts.com/i-24134684-sdpc-gen-vi-big-block-chevrolet-diverter-fitting.html


Hot Rod shows it the way I'm understanding it where the oil leaves the engine from the rear port, enters the bottom of the cooler, exits the top of the cooler then returns through the front port.

https://www.hotrod.com/articles/run-gen-v-vi-big-block-chevy-without-oil-cooler/

So the oil is being pumped from bottom to top in the cooler?

Thanks in advance.

 

[alpinecrick]

My understanding is on all the GM integrated coolers in the radiator the fluid is pumped from bottom to top. This applies to both engine oil cooler and trans cooler.

 

[Schurkey]

My understanding is on all the GM integrated coolers in the radiator the fluid is pumped from bottom to top. This applies to both engine oil cooler and trans cooler.

Yup. Having the fluids moving opposite directions (oil or ATF moving "up" while the coolant is moving "down" increases the efficiency of the cooler.

You could have the oil moving the same direction as the coolant, and the thing will still "work"--but it doesn't cool as well.

I've heard 10% increase in efficiency--but that's not confirmed; and I heard it in reference to a cooler used on a City Bus.