Catch can anybody running one on the new HD

L8T · January 27, 2021

Also what are the symptoms of carboned up intake valves? Wife’s DI car has 80 000 miles on it and I don’t know if it’s ever been cleaned.

D A · January 27, 2021

16 hours ago, L8T said:

Also what are the symptoms of carboned up intake valves? Wife’s DI car has 80 000 miles on it and I don’t know if it’s ever been cleaned.

Loss of power especially when driving at higher speed.
Poor acceleration.
Cold stalling.
Engine misfires.
Reduced fuel efficiency.
Check engine light turned on.
Rough running.
Engine judder at idle speed.

djxn40 · March 28, 2021

On 1/26/2021 at 8:46 PM, D A said:

I’m not against a catch can but would be concerned over a denial of warranty with the addition of a catch can. I lack the financial resources to take GM to court. Not sure if Magnuson Moss would work or not. It seems from spending way too much time reading about this subject that timely oil changes and using the correct oil goes a long way to help.

My warranty would be fine. Just like the warranty on my last truck that was tuned. When I took it to the dealer I reverted it to stock. Just re install the stock line and no sign of a catch can. People tend to freak out thinking gm tries to find a reason not to warranty. My 2018 was tuned and had a catch can. First they replaced my engine and exactly 1 year later they replaced my transmission. Never mentioned anything to me about aftermarket parts.

Edited March 28, 2021 by djxn40

gridjockey · April 19, 2021

the new 6.6 gas has two pvc valves one for each valve cover. you will need a catch can with a double hookup or two cans. you will need a cap for the air plenum fitting above the throttle body. you will need a carb sticker in california

Hoginedgewood · August 13, 2022

I bought a 22 2500HD with a 6.6 gas, I see the hose a previous poster put a catch can on, it runs to the intake manifold I believe. On the other valve theres a much larger hose going into the air box.

so I question weather the small hose goes in the intake manifold or under it, and I think the big hose on the passenger side is the most important for a catch can.

Epsilon Plus · September 3, 2022

Based on the storied history of the 6.0, used to 300,000mi in fleets around the US and routinely over 200,000mi in personal customers hands, added to the fact that it had a worse (lack of) internal catch system than the L8T the following can be surmised:

If you change your oil at the first 500 miles, and every 3,000 after and use a catch can, your engine will last 250,000+mi

If you change your oil at 7,500 or the OLM warning, and don't use a catch can, your engine will only last 250,000+mi.

You also probably won't be one of the 5% of people that keep the truck that long. All y'all are keeping it mighty nice for the second and third owners.

Edited September 3, 2022 by Epsilon Plus

Jettech1 · December 4, 2022

On 9/3/2022 at 9:42 AM, Epsilon Plus said:

Based on the storied history of the 6.0, used to 300,000mi in fleets around the US and routinely over 200,000mi in personal customers hands, added to the fact that it had a worse (lack of) internal catch system than the L8T the following can be surmised:

If you change your oil at the first 500 miles, and every 3,000 after and use a catch can, your engine will last 250,000+mi

If you change your oil at 7,500 or the OLM warning, and don't use a catch can, your engine will only last 250,000+mi.

You also probably won't be one of the 5% of people that keep the truck that long. All y'all are keeping it mighty nice for the second and third owners.

That is a great point you make. I installed the JLT, well now JL catch can on my 2022 2500 custom when I first bought it and I think you are absolutely right. I'm just making sure it is perfect for the next owner. LOL.....You win.....lol....

C/K Man · December 13, 2022

Keep in mind that a lot of intake valve/port deposits are not caused by oil going through the PCV system. Modern engines with VVT advance cam timing to create EGR rather than have a separate EGR valve and system. By opening the intake valve before the piston reaches TDC on the exhaust stroke some exhaust is pushed up into the intake port for a brief instant before it gets drawn back into the cylinder on the intake stroke.. That hot exhaust will condense on the back of the relatively cool intake valve and in the port just above it, creating deposits. As you know port fuel injection does a very good job of keeping the intake valve and port clean. So, with any DI engine it might be a good idea to periodically use an intake valve/port cleaner even if you install a catch-can.

Pryme · December 13, 2022

For the guys who have put a catch can on their 6,6 gas, do you pull oil out of it often?

I know it’s supposed to have a separator built into the engine.

Edited December 13, 2022 by Pryme

Jettech1 · December 13, 2022

54 minutes ago, Pryme said:

For the guys who have put a catch can on their 6,6 gas, do you pull oil out of it often?

I know it’s supposed to have a separator built into the engine.

It's a little late right now but tomorrow I'll take a pic of what's in mine. I think I have about 2k miles on it since I had the first oil change at 2500 miles. I installed mine at 300 miles and at 2500 miles there was maybe an ounce in it. I haven't looked at it since but will certainly look at it tomorrow and post a pic for you. You've got me curious as well.

Jettech1 · December 13, 2022

22 minutes ago, Jettech1 said:

1 hour ago, Pryme said:

For the guys who have put a catch can on their 6,6 gas, do you pull oil out of it often?

I know it’s supposed to have a separator built into the engine.

It's a little late right now but tomorrow I'll take a pic of what's in mine. I think I have about 2k miles on it since I had the first oil change at 2500 miles. I installed mine at 300 miles and at 2500 miles there was maybe an ounce in it. I haven't looked at it since but will certainly look at it tomorrow and post a pic for you. You've got me curious as well.

Well the suspense was killing me. So I took a pic of what is in my catch can and I can honestly say I wasn't expecting that much oil in it. I'm just shy of 2k miles since it was last emptied at the 2500 mile oil change. There is a little over an ounce, 1.2 to be exact in the catch can. Most of my driving is city and some highway. I would say probably 80% city, 20% highway. No towing since I had the oil change. I'm actually quite surprised how much it was. I'm glad I looked. Thanks for the idea!!! It appears to me that a catch can is probably a really good idea on these engines.

Pryme · December 13, 2022

7 hours ago, Jettech1 said:

Well the suspense was killing me. So I took a pic of what is in my catch can and I can honestly say I wasn't expecting that much oil in it. I'm just shy of 2k miles since it was last emptied at the 2500 mile oil change. There is a little over an ounce, 1.2 to be exact in the catch can. Most of my driving is city and some highway. I would say probably 80% city, 20% highway. No towing since I had the oil change. I'm actually quite surprised how much it was. I'm glad I looked. Thanks for the idea!!! It appears to me that a catch can is probably a really good idea on these engines.

Thank you. That looks like a lot you’re right. So I read someone here saying you would need one on each side for a total of two? Is that correct?

which catch can did you go with

Jettech1 · December 13, 2022

1 hour ago, Pryme said:

Thank you. That looks like a lot you’re right. So I read someone here saying you would need one on each side for a total of two? Is that correct?

which catch can did you go with

I only have one, never heard of 2 being needed for any engine. I always use JL catch cans. They run about 150 on Amazon and are super easy to install.

Pryme · December 13, 2022

8 hours ago, Jettech1 said:

I only have one, never heard of 2 being needed for any engine. I always use JL catch cans. They run about 150 on Amazon and are super easy to install.

A guy 10 posts back, gridjockey, said there is a pcv valve on each valve cover which would each need a can?