Still Don't Think You Need A Catch Can?

ProModMike · March 27, 2016

This is on a 2015 Denali 1500 w/6.2 @11,400 miles. The can was installed @10,000 miles. The oil life meter still reads 72%. Proof is right here. Even if gas was still washing over the valves, I still wouldn't want all this in the intake.

codman232 · March 27, 2016

This is what I don't understand. If they know this is an issue with DI engines, why doesn't GM intall this as a permanent fix? Without a catch can I think the trucks with DI engines will have longevity issues. Why would anyone want to pay for a 50k dollar truck with known issues and the thought it might not last 120k miles? This is insanity!

UplandPa · March 27, 2016

A different perspective!

good post from mike at Criswell, a forum dealer - after reading this, I took mine off and sold it.

Written to mike at Criswell when he asked one of his GM/Corvette engineering buddies about this…

MIke: "I was the one that contacted someone from the Stingray Consultant team from GM...Here comes is what he wrote back on this matter."

"The Stingray was evaluated with over one million development miles on 200 captured test fleet cars. There are tens of thousands of direct injection vehicles on the road from General Motors alone. During the evaluation hundreds of engines were literally torn down in to part piles and evaluated. There are hundreds of thousands of LSx family of motors (where part of this catch can hype started) on the roads and the many of these motors are running well past 250,000 miles without a catch can.

The cars have a 100,000 mile powertrain warranty and that includes mechanical failure of the engine. Trust me when I tell you that there are not reams of data (not even pages of data) on cars coming up lame because of oil at the MAF. It just isn't the problem that the "internet" makes it out to be. When you ask a GM Powertrain engineer about a catch can the reply is that the only thing you get is added weight.

In looking at the extra effort and added cost that went in to the Stingray, do you really believe for one second that if a $20.00 part attached to the engine would improve reliability, limit warranty claims and replacement costs, that GM wouldn't have put it on if it was necessary as part of their evaluation?

Every single GM engineer that I have spoken with told me in one form or another that a catch can is predominately a "gimmick" device created by tuners looking to make a few extra bucks on their engine modifications.

As a by-product of the PCV system, excess oil vapor is recycled to prevent it from leaching out in to the environment. It will condense back in to liquid if the temperature and environmental conditions are right. A catch can is an oil separator device. It allows the heavier oil in liquid to condense in the bottom of the can and only pass the air (gases) back. This is basically the same thing that is happening at the front of the MAF where most of the oil can be found.

The theory is that this oil in the intake system will collect on the valves and in the cylinders and cause excess carbon deposits. The catch can will reduce (not eliminate) oil pooling in the MAF.

Where the plan breaks down is that there aren't thousands of cars detonating because of the oil. As I told you on the phone, This isn't new. The engines are designed to deal with a quantity of oil mist presented via the intake.

You asked what I should tell the customer, my answer is I'm not sure because I don't know what his question is. If the question is is this normal? The answer is yes. If the question is should I put a catch can on? The answer is what ever makes you feel better. If the question is do I need a catch can? The answer is a resounding no. If the reply is that they saw it on the internet, apologize politely and tell them virtually every thread about it has started with a vendor selling a product or a consumer that was fooled by the hype and trying to make themselves feel better about their purchase by getting others to agree with them.

If he has concerns about his condition he should take the car to his dealer for evaluation.

Here is my standard response to the dozens of emails I get each year with a link to a thread like you posted (and often, that very same thread).

Simply stated, absolutely not on the catch can. It simply isn’t warranted for any street driven car. We can talk in more detail about it tomorrow and Dan will appreciate it as I’ve all ready had this conversation with him as well. Since the advent of the PCV system, cars have released some oil in places where it wouldn’t normally have gone in a fully sealed system. It ends up in vapor which condenses back in to liquid form in the intake path. As a result of that, the system is designed to ingest and subsequently digest some extra oil. Higher revving produces more oil and repeated higher revving (drag racer, track duty car, etc.) would be in the realm of uses that I might consider adding the can. Daily driving, occasional back road romp or stop light to stop light burst, not so much.

With all of that said, they won’t hurt anything. For those that don’t want to take my word for it, can feel comfortable adding it but it won’t make an appreciable difference in the life of the motor or the efficiency of the system.
If you dig deep enough in to forum information about catch cans, all roads generally lead back to a performance tuner, aftermarket part supplier or fabricator who has a vested interest in selling catch cans." Stingray Consultant

Silverado4x4 · March 27, 2016

A different perspective!

good post from mike at Criswell, a forum dealer - after reading this, I took mine off and sold it.

Written to mike at Criswell when he asked one of his GM/Corvette engineering buddies about this…

MIke: "I was the one that contacted someone from the Stingray Consultant team from GM...Here comes is what he wrote back on this matter."

"The Stingray was evaluated with over one million development miles on 200 captured test fleet cars. There are tens of thousands of direct injection vehicles on the road from General Motors alone. During the evaluation hundreds of engines were literally torn down in to part piles and evaluated. There are hundreds of thousands of LSx family of motors (where part of this catch can hype started) on the roads and the many of these motors are running well past 250,000 miles without a catch can.

The cars have a 100,000 mile powertrain warranty and that includes mechanical failure of the engine. Trust me when I tell you that there are not reams of data (not even pages of data) on cars coming up lame because of oil at the MAF. It just isn't the problem that the "internet" makes it out to be. When you ask a GM Powertrain engineer about a catch can the reply is that the only thing you get is added weight.

In looking at the extra effort and added cost that went in to the Stingray, do you really believe for one second that if a $20.00 part attached to the engine would improve reliability, limit warranty claims and replacement costs, that GM wouldn't have put it on if it was necessary as part of their evaluation?

Every single GM engineer that I have spoken with told me in one form or another that a catch can is predominately a "gimmick" device created by tuners looking to make a few extra bucks on their engine modifications.

As a by-product of the PCV system, excess oil vapor is recycled to prevent it from leaching out in to the environment. It will condense back in to liquid if the temperature and environmental conditions are right. A catch can is an oil separator device. It allows the heavier oil in liquid to condense in the bottom of the can and only pass the air (gases) back. This is basically the same thing that is happening at the front of the MAF where most of the oil can be found.

The theory is that this oil in the intake system will collect on the valves and in the cylinders and cause excess carbon deposits. The catch can will reduce (not eliminate) oil pooling in the MAF.

Where the plan breaks down is that there aren't thousands of cars detonating because of the oil. As I told you on the phone, This isn't new. The engines are designed to deal with a quantity of oil mist presented via the intake.

You asked what I should tell the customer, my answer is I'm not sure because I don't know what his question is. If the question is is this normal? The answer is yes. If the question is should I put a catch can on? The answer is what ever makes you feel better. If the question is do I need a catch can? The answer is a resounding no. If the reply is that they saw it on the internet, apologize politely and tell them virtually every thread about it has started with a vendor selling a product or a consumer that was fooled by the hype and trying to make themselves feel better about their purchase by getting others to agree with them.

If he has concerns about his condition he should take the car to his dealer for evaluation.

Here is my standard response to the dozens of emails I get each year with a link to a thread like you posted (and often, that very same thread).

Simply stated, absolutely not on the catch can. It simply isn’t warranted for any street driven car. We can talk in more detail about it tomorrow and Dan will appreciate it as I’ve all ready had this conversation with him as well. Since the advent of the PCV system, cars have released some oil in places where it wouldn’t normally have gone in a fully sealed system. It ends up in vapor which condenses back in to liquid form in the intake path. As a result of that, the system is designed to ingest and subsequently digest some extra oil. Higher revving produces more oil and repeated higher revving (drag racer, track duty car, etc.) would be in the realm of uses that I might consider adding the can. Daily driving, occasional back road romp or stop light to stop light burst, not so much.

With all of that said, they won’t hurt anything. For those that don’t want to take my word for it, can feel comfortable adding it but it won’t make an appreciable difference in the life of the motor or the efficiency of the system.
If you dig deep enough in to forum information about catch cans, all roads generally lead back to a performance tuner, aftermarket part supplier or fabricator who has a vested interest in selling catch cans." Stingray Consultant

I agree with this statement 100%. People fall for these gimmicks all the time.

BTW Mike said his oil life monitor is still at 72% this has nothing to do with the oil its a reading from the computer on how you drive the vehicle that gives you oil life % the OLM doesn't sample the oil and give you a percentage of oil life left.

Jeff5347 · March 27, 2016

I agree to extent on this. I for one have had a catch can on my last vehicle and on the Silverado now since 1000 miles. The act of oil going into the catch can thru the pcv valve is not something new. I've had plenty of vehicles with built engines that all incorporated at PVC system or just a breather. If you look at vehicles with a breather that is in a modified engine 350, 454, 383 and that engine is built meaning high compression, larger can, ignition, ect you get more pressure inside the engine. A sealed engine, meaning no PVC or anything that leaves no opening to the outside world, pressure builds and seals can be blown by way of rear main seals , front seals, ect. Also the PVc as stated takes this mist of oil and recycles it thru the engine to be burnt and not dripped all over the pavement. Now back to a breather... And that being on a very modified engine after a while the oil starts to leak due to the foam being saturated with the oil and no where else to go. I for one believe that as the oil gets recycled back thru the intake and to the combustion chamber it does in essence lower the flash point and create detonation , pinging and such, albeit if the vehicle is maintained properly this can be avoided and lessened. My take is I like having the catch can. Is it needed?...who knows , I'm not an engineer . does it give me a placebo effect of piece of mind? ....for me yes, I can see at 1000 miles I have oil in the can that is not getting recycled in to the engine to reduce performance and increase maintenance needs.

So just like someone saying you look good today. Maybe your still ugly as sin but that one thing just made the day a bit better...even if it isn't true.

Sent from my Nexus 6P using Tapatalk

Tony Bianco · March 27, 2016

I've never used them on any of the GM cars I've owned over the past 35 years.

Never any problem with engines, ever. Average mileage I've put on my vehicles is over 300K.

These engines are obviously engineered and designed to function properly with what others view to be serious issues.

Oil catch cans are warranted in high performance engines, but more of a gimmick for consumer vehicles, IMHO.

Tek74 · March 27, 2016

why doesn't GM intall this as a permanent fix?

Either GM doesn't feel that catch cans are necessary and/or GM knows that if they installed them on DI vehicles, many or most customers won't drain them at regular intervals.

I spent a couple months reading a ton of info on catch cans from various sources and decided that $150 was not a huge investment for a little extra piece of mind for a truck that I intend to keep for 10+ years. Maybe it will help and maybe it won't.

cato · March 27, 2016

Good info here!

Thanks for posting.

entreri · March 27, 2016

A different perspective!

good post from mike at Criswell, a forum dealer - after reading this, I took mine off and sold it.

Written to mike at Criswell when he asked one of his GM/Corvette engineering buddies about this…

MIke: "I was the one that contacted someone from the Stingray Consultant team from GM...Here comes is what he wrote back on this matter."

"The Stingray was evaluated with over one million development miles on 200 captured test fleet cars. There are tens of thousands of direct injection vehicles on the road from General Motors alone. During the evaluation hundreds of engines were literally torn down in to part piles and evaluated. There are hundreds of thousands of LSx family of motors (where part of this catch can hype started) on the roads and the many of these motors are running well past 250,000 miles without a catch can.

The cars have a 100,000 mile powertrain warranty and that includes mechanical failure of the engine. Trust me when I tell you that there are not reams of data (not even pages of data) on cars coming up lame because of oil at the MAF. It just isn't the problem that the "internet" makes it out to be. When you ask a GM Powertrain engineer about a catch can the reply is that the only thing you get is added weight.

In looking at the extra effort and added cost that went in to the Stingray, do you really believe for one second that if a $20.00 part attached to the engine would improve reliability, limit warranty claims and replacement costs, that GM wouldn't have put it on if it was necessary as part of their evaluation?

Every single GM engineer that I have spoken with told me in one form or another that a catch can is predominately a "gimmick" device created by tuners looking to make a few extra bucks on their engine modifications.

As a by-product of the PCV system, excess oil vapor is recycled to prevent it from leaching out in to the environment. It will condense back in to liquid if the temperature and environmental conditions are right. A catch can is an oil separator device. It allows the heavier oil in liquid to condense in the bottom of the can and only pass the air (gases) back. This is basically the same thing that is happening at the front of the MAF where most of the oil can be found.

The theory is that this oil in the intake system will collect on the valves and in the cylinders and cause excess carbon deposits. The catch can will reduce (not eliminate) oil pooling in the MAF.

Where the plan breaks down is that there aren't thousands of cars detonating because of the oil. As I told you on the phone, This isn't new. The engines are designed to deal with a quantity of oil mist presented via the intake.

You asked what I should tell the customer, my answer is I'm not sure because I don't know what his question is. If the question is is this normal? The answer is yes. If the question is should I put a catch can on? The answer is what ever makes you feel better. If the question is do I need a catch can? The answer is a resounding no. If the reply is that they saw it on the internet, apologize politely and tell them virtually every thread about it has started with a vendor selling a product or a consumer that was fooled by the hype and trying to make themselves feel better about their purchase by getting others to agree with them.

If he has concerns about his condition he should take the car to his dealer for evaluation.

Here is my standard response to the dozens of emails I get each year with a link to a thread like you posted (and often, that very same thread).

Simply stated, absolutely not on the catch can. It simply isn’t warranted for any street driven car. We can talk in more detail about it tomorrow and Dan will appreciate it as I’ve all ready had this conversation with him as well. Since the advent of the PCV system, cars have released some oil in places where it wouldn’t normally have gone in a fully sealed system. It ends up in vapor which condenses back in to liquid form in the intake path. As a result of that, the system is designed to ingest and subsequently digest some extra oil. Higher revving produces more oil and repeated higher revving (drag racer, track duty car, etc.) would be in the realm of uses that I might consider adding the can. Daily driving, occasional back road romp or stop light to stop light burst, not so much.

With all of that said, they won’t hurt anything. For those that don’t want to take my word for it, can feel comfortable adding it but it won’t make an appreciable difference in the life of the motor or the efficiency of the system.

If you dig deep enough in to forum information about catch cans, all roads generally lead back to a performance tuner, aftermarket part supplier or fabricator who has a vested interest in selling catch cans." Stingray Consultant

I agree with this statement 100%. People fall for these gimmicks all the time.

BTW Mike said his oil life monitor is still at 72% this has nothing to do with the oil its a reading from the computer on how you drive the vehicle that gives you oil life % the OLM doesn't sample the oil and give you a percentage of oil life left.

I couldnt agree more with this post. As a former parts expert I remember many of these types of gimmicks/gadgets that have a place in the TRUE high performance arena being marketed to everyone and making the manufacturers and the stores I worked for a lot of money. Most who will put this on a vehicle wont put enough miles on before getting another vehicle to ever have worried about it to begin with. All that said if it makes you feel better than go for it. The internet will help you feel justified about it in some forums in others it will make you feel as though your a fool for doing it that is what the internet is a place where almost any idea or opinion can be justified if you look hard enough.

I have had many many GM and other vehicles over the years with more mileage than I could have imagined and this is the least thing I would worry about.

peejaykay · March 27, 2016

I'm not a SAE mechanic, but I'm also of the opinion that marketing is what's working here. Catch cans are HUGE profit margin items that sell for more than $200 is some cases. Hence, alot of misinformation as to why you NEED it or your engine is going to self destruct over time.

Tek74 · March 27, 2016

I would agree that only time will tell if catch cans really benefit these DI engines or not. When there are enough 100k+ mile DI engines run WITH and WITHOUT catch cans, then they can be opened up, inspected, and compared.

I see catch cans as just one more thing to maybe help over the long haul. Aside from running one, I also do other little things to help maintain optimal engine performance and extend engine life. I run high quality synthetic oil, I only use Top Tier gas, I run a bottle of Chevron Techron fuel system cleaner every 4k-5k miles, and a do a quick 2nd gear Italian Tune-Up once per day once the engine is fully warmed up.

ProModMike · March 27, 2016

I agree to extent on this. I for one have had a catch can on my last vehicle and on the Silverado now since 1000 miles. The act of oil going into the catch can thru the pcv valve is not something new. I've had plenty of vehicles with built engines that all incorporated at PVC system or just a breather. If you look at vehicles with a breather that is in a modified engine 350, 454, 383 and that engine is built meaning high compression, larger can, ignition, ect you get more pressure inside the engine. A sealed engine, meaning no PVC or anything that leaves no opening to the outside world, pressure builds and seals can be blown by way of rear main seals , front seals, ect. Also the PVc as stated takes this mist of oil and recycles it thru the engine to be burnt and not dripped all over the pavement. Now back to a breather... And that being on a very modified engine after a while the oil starts to leak due to the foam being saturated with the oil and no where else to go. I for one believe that as the oil gets recycled back thru the intake and to the combustion chamber it does in essence lower the flash point and create detonation , pinging and such, albeit if the vehicle is maintained properly this can be avoided and lessened. My take is I like having the catch can. Is it needed?...who knows , I'm not an engineer . does it give me a placebo effect of piece of mind? ....for me yes, I can see at 1000 miles I have oil in the can that is not getting recycled in to the engine to reduce performance and increase maintenance needs.

So just like someone saying you look good today. Maybe your still ugly as sin but that one thing just made the day a bit better...even if it isn't true.

Sent from my Nexus 6P using Tapatalk

^^^This. I have an evac system on my pro-mod in my avatar. It has that because, well, it has a 16:5:1 compression ratio and spins at 9,000rpm. Does my truck have or do either? Nope. So what? I completely understand the OLM doesn't actually sample the oil to determine the percentage. My masters in mechanical engineering tells me there isn't a chromatograph inside the engine. All I was trying to do with this post was present MY experience with a certain product and my findings. The intent was NOT to insinuate that GM engineers are stupid and that if people don't have a catch can, their truck will blow up. I paid $85 for the ADD W1 catch can from eBay. So for $85 I know for the next 5 years at least and however many miles, I'm not going to have at least that much oil per 1,000 miles go through my motor. Good enough for the girls I go out with.

I agree to extent on this. I for one have had a catch can on my last vehicle and on the Silverado now since 1000 miles. The act of oil going into the catch can thru the pcv valve is not something new. I've had plenty of vehicles with built engines that all incorporated at PVC system or just a breather. If you look at vehicles with a breather that is in a modified engine 350, 454, 383 and that engine is built meaning high compression, larger can, ignition, ect you get more pressure inside the engine. A sealed engine, meaning no PVC or anything that leaves no opening to the outside world, pressure builds and seals can be blown by way of rear main seals , front seals, ect. Also the PVc as stated takes this mist of oil and recycles it thru the engine to be burnt and not dripped all over the pavement. Now back to a breather... And that being on a very modified engine after a while the oil starts to leak due to the foam being saturated with the oil and no where else to go. I for one believe that as the oil gets recycled back thru the intake and to the combustion chamber it does in essence lower the flash point and create detonation , pinging and such, albeit if the vehicle is maintained properly this can be avoided and lessened. My take is I like having the catch can. Is it needed?...who knows , I'm not an engineer . does it give me a placebo effect of piece of mind? ....for me yes, I can see at 1000 miles I have oil in the can that is not getting recycled in to the engine to reduce performance and increase maintenance needs.

So just like someone saying you look good today. Maybe your still ugly as sin but that one thing just made the day a bit better...even if it isn't true.

Sent from my Nexus 6P using Tapatalk

^^^This. I have an evac system on my pro-mod in my avatar. It has that because, well, it has a 16:5:1 compression ratio and spins at 9,000rpm. Does my truck have or do either? Nope. So what? I completely understand the OLM doesn't actually sample the oil to determine the percentage. My masters in mechanical engineering tells me there isn't a chromatograph inside the engine. All I was trying to do with this post was present MY experience with a certain product and my findings. The intent was NOT to insinuate that GM engineers are stupid and that if people don't have a catch can, their truck will blow up. I paid $85 for the ADD W1 catch can from eBay. So for $85 I know for the next 5 years at least and however many miles, I'm not going to have at least that much oil per 1,000 miles go through my motor. Good enough for the girls I go out with.

Daryl LBZ · March 27, 2016

This is what I don't understand. If they know this is an issue with DI engines, why doesn't GM intall this as a permanent fix? Without a catch can I think the trucks with DI engines will have longevity issues. Why would anyone want to pay for a 50k dollar truck with known issues and the thought it might not last 120k miles? This is insanity!

They're probably afraid that no one will ever drain them. A lot of people have never heard the words "preventative maintenance" when it comes to a vehicle.

glcbn · March 27, 2016

They're probably afraid that no one will ever drain them. A lot of people have never heard the words "preventative maintenance" when it comes to a vehicle.

This IMO, is the main reason they aren't factory installed. Just like if GM put a section in the 5.3 manual "recommending" you to use higher octane fuel. It's high compression too, and would benefit as much as the 6.2. Heck, most people have never opened their manual from day one.

Is a catch can a gimmick. Personally I don't think so. But we won't know if it really makes a difference until we see how high mile vehicles are performing. It would be nice to see a test comparison of two identical engines after 100,000 miles. One with, the other without a can. I doubt the makers would do this, but I'm surprised an independent hadn't done this yet.