Oil/air separator *catch can

Half_ton · March 23, 2020

Hey folks,

Just got my 6.6 gasser GMC home and ordered the regular stuff (mats, tonneau, new ceramic coating, center console organizer, etc) and I am moving the mods from my 2015 1/2 ton over such as sub/amp and my catch can.

That being said, has anyone hooked up a catch can to their 6.6 L8T?

I have the moroso can, but literally haven't opened the hood for more than 3 min.

Does anyone have a diagram of the pcv lines on the new 6.6?

Any pictures of installs?

Thanks in advance,

Jay

-David- · April 19, 2020

Bump. I am also interested in this as well.

Jay, were you able to find more information that you can post?

As I understand, GM has patented a 2-stage oil/air separator system. I have found no positive indication that this new system is used on the L8T 6.6 gas engine. Does anyone know if the GM L8T 6.6 gas engine incorporates the new patented 2 stage oil separating system?

A Chevrolet engineer being interviewed by Mr. Truck at 17:30 minutes briefly discussed an oil/air separator being built into the L8T 6.6 gas engine PCV system and he says that it will "completely" remove the oil from air entering the induction system and that only exhaust by-products are returned to be burned. This raises questions:

Does "completely" mean 100% oil removal (no can required)?

Has anyone installed a catch can on a L8T 6.6 and is catching oil in it?

Has anyone pulled the PCV hoses off of the new 6.6 and has found oil passing into the air intake?

Thanks

David

Rand Richards · July 20, 2020

Ohh God I'm interested in this. Since towing is going to result in high loaded rpm's for the 6.6 gas. I was thinking about an oil catch can might be necessary

C/K Man · July 30, 2020

My understanding is the 6.6L has the oil/air separator built into the valve covers like the DI 4.3/5.3/6.2 engines do. I don't think a 'catch can' in needed.

gridjockey · April 19, 2021

there are two pcv valves on the new 6.6 gas one on each valve cover up front by the throttle body. you will need a carb sticker in california or remove it at service or smog inspection.you will need to cap fitting on air intake.