I would like to start a NEW catch can post for all to follow.

[Chuck FB]

On 4/7/2025 at 7:57 PM, lineman1234 said:

How much oily water can you catch between your preferred oil change intervals. On your L8T 6.6 gasser. 

 

Or maybe we should start a contest.                                                     ( or not )

 

About 3 tanks of gas on the can pic. Miles and how long a tank varies for me. Temps at or below freezing seem to collect a lot more water than summer temps. Its a 3oz can. 

       Should be warming up hear in the very north soon, so it will be more oil per water, vs more water per oil now. . 

 

Towing and or driving long distances are much less. Just seems to catch and save on my shorter trips. 

 

I spent most the winter on the gulf coast of Texas, and much less is in the can per tanks. But it likes to pull water out up north hear in the cold. 

 

 

Is a catch can needed on the L8T, NO, does it catch stuff, yep, would the water be burnt off sooner or later, YEP. 

       I do like that its not dumping the moister into the drivers side valve cover though. Or less of it. 

Had you poured that into a glass jar for example and let it settle, viewing it from the surface shows the oil floating on water or, really no way of telling how much oil vs water unless its able to settle and see a side view of the proportions. I am only speculating that colder temps as per the air flow within the engine compartment help to condense the airborne water vapour back into liquid droplets and collect quicker in the container vs one cold start and a loaded engine that gets the temps up better, engine oil, engine compartment etc to carry the water as vapour right through that canister and into the intake. I've seen on other forums or youtube channels, experimenting with a catch can and having a surprise result the moment the weather turns colder/below freezing and not a good surprise as per may be not even catching it in time due to the volume of water and it freezing plugging off the exist for the crank case system. Probably works quite fine in area's that never experience frost but up here where I am in Canada I don't hear guys talking about their catch cans as its just too risky of a venture to play with.

[Pryme]

There are hundreds of thousands of hard working HD pickups racking up hundreds of thousands of miles all over the country. Not a single one has a “catch can”

 

imagine out on the oil patch. 
 

he butch, we need you out at that new well being drilled. 
yeah, give me a minute I have to check my catch can. 
 

“butch, you’re fired”

[lineman1234]

If not interested, dont be. Some people are. 

 

As always............   Is it needed NOPE...   Does it catch stuff, yep. That i have proven. Not just blindly commented on the subject. 

 

Do my mirrors rattle. NOPE. do i comment on the rattling mirror thread. NOPE. 

 

Do i need a second battery, nope, do i have one, yep. 

[lineman1234]

11 hours ago, Chuck FB said:

Had you poured that into a glass jar for example and let it settle, viewing it from the surface shows the oil floating on water or, really no way of telling how much oil vs water unless its able to settle and see a side view of the proportions. I am only speculating that colder temps as per the air flow within the engine compartment help to condense the airborne water vapour back into liquid droplets and collect quicker in the container vs one cold start and a loaded engine that gets the temps up better, engine oil, engine compartment etc to carry the water as vapour right through that canister and into the intake. I've seen on other forums or youtube channels, experimenting with a catch can and having a surprise result the moment the weather turns colder/below freezing and not a good surprise as per may be not even catching it in time due to the volume of water and it freezing plugging off the exist for the crank case system. Probably works quite fine in area's that never experience frost but up here where I am in Canada I don't hear guys talking about their catch cans as its just too risky of a venture to play with.

Glass, no, an old plastic milk jug, yep. Just separates water, oily gassy stuff, and oil different layers, not much but a little gunk at the bottom.

    Just for one oil change interval. No need to do it again. 

     Mostly water, some unburnt fuel smell, some burnt fuel smell, and oil, as well at times, some gunky stuff on the bottom that needs wiping out. 

[Chuck FB]

42 minutes ago, lineman1234 said:

If not interested, dont be. Some people are. 

 

As always............   Is it needed NOPE...   Does it catch stuff, yep. That i have proven. Not just blindly commented on the subject. 

 

Do my mirrors rattle. NOPE. do i comment on the rattling mirror thread. NOPE. 

 

Do i need a second battery, nope, do i have one, yep. 

I typed this before your last comment, but the same logical thought process remains as per why I decided the risk was higher than the reward due to being stuck in the arctic ! ( or so it seems some winter days )

 

If directed at myself my intent was not to bash catch cans as the principle behind it is the very same thing the manufacture is attempting to do by way of fancy baffling in the valve covers etc. The problem is those systems are not capable of separating 100% of the oil out as you proved with the catch can. I've seen a lot of comments from farmers for example and others in Australia, a catch can on their diesel ute is the go to aftermarket item they will put on their vehicle because it catches oil and for the most part in Australia they don't have to worry about freezing temps causing an issue. Diesel engines never had this issue back when they had an external pipe to vent off the moisture and yes some oil vapour as well. Gas engines were fairly able to cope with the oil in the intake when they had a carb, throttle body, port injection ... until the direct injection took away the ability to keep the intake and the back side of the intake valves washed clean. Mind you the cat has to deal with the oil issue and not sure how well it likes that.

 

Before I bought my truck I was looking into the idea of a catch can but it always came back to winter time and the risk of running one causing a major mess with blowing out seals and gaskets if not serviced extremely often as in every week from what I gather. We have the same issues with the typical gas engines on grain augers, the hose from the crank case to the intake manifold can plug with ice and then something has to give and guys have had a crank seal blow and the oil fly out of the crankcase in a dramatic way and unless caught and shut down, that is the end of the engine unless it has a oil pressure sensor ( which often is disconnected because of starting in cold weather and that fights against starting as there is no spark until there is oil pressure ).

 

Edited April 10, 2025 by Chuck FB

[Chuck FB]

26 minutes ago, lineman1234 said:

Glass, no, an old plastic milk jug, yep. Just separates water, oily gassy stuff, and oil different layers, not much but a little gunk at the bottom.

    Just for one oil change interval. No need to do it again. 

     Mostly water, some unburnt fuel smell, some burnt fuel smell, and oil, as well at times, some gunky stuff on the bottom that needs wiping out. 

As I think of our older trucks and tractors with either a steel pipe or a hose that dangles down and an oily scum that slowly accumulates and surrounds the exit of the pipe or puts the vapour onto the front axle of a four wheel drive tractor and then dirt sticks to it so it looks like far more of an issue than it really is. Its what I have been used to for so many years with said equipment and in fact our JD combines use the crankcase vapour pipe to drain the engine oil from the crankcase into that pipe and catch the oil with pails at the ground level so they turned the breather line into a multi use item.

 

I would expect as an engine would get ring wear, the oil and water accumulation will increase, just the nature of the beast with the life of an internal combustion engine. It would be rather nasty foul smelling stuff that would accumulate, combustion byproducts along with the oil, in fact it may even smell a bit like what some crude smells like when it comes out of the ground ... go figure !

[Chuck FB]

1 hour ago, Pryme said:

There are hundreds of thousands of hard working HD pickups racking up hundreds of thousands of miles all over the country. Not a single one has a “catch can”

 

imagine out on the oil patch. 
 

he butch, we need you out at that new well being drilled. 
yeah, give me a minute I have to check my catch can. 
 

“butch, you’re fired”

As funny as that scenario may sound, I think the fact is that its the rest of the crap emissions system on the newer diesels that is causing the major issues of breakdown/delays. Its probably a couple of years ago now that I had an unrelated issue with one of my highway tractors and took it to a mechanic shop in the area and he would be under contract for one oil field company but also is able to accept anything else as well into his shop when there is time. He estimated then that he had probably done 200 deletes in that year alone on highway tractors, mostly Cummins. He points to a truck still hooked to a trailer sitting in his yard and said that one came limping in and its due for a delete. Major issues constantly it seems with all this crap they have thrown at these diesels and at least here in Alberta there hasn't been a huge push to stop the "repairs" for those trucks that run locally anyway ( couldn't say about those cross Canada transport trucks ).

 

Its more plausible that Butch is sitting at the Kenworth or Peterbilt dealer if an owner operator when he phone rang, getting sensors replaced on his DEF system or just got the news that a whole engine rebuild is in order to keep "truckin"

[lineman1234]

Awful quiet on the catch can area. 

 

I took this pic a few weeks ago. I dont track when i dump the can or measure whats in it, or send it off for analysis. 

        I wipe it out from time to time, mostly just dump it, sometimes no ( stuff ) in there, sometimes there is ( stuff ) in there. 

        Is that stufffffff, sludge? Or, just stuff. 

        The liquid that was in there had been dumped, then i took the pic's then wiped out the can. 

 

 

[No F-bdy Bs]

Blows my mind that this topic is 7 pages long, but you mention the Allison 10spd valve body, and people are like "eh (shrug) what can ya do, eh?" 

 

Still an amazing lack of info on a $10,000 trans that locks up the rear wheels just,,, whenever. 

[lineman1234]

2 hours ago, No F-bdy Bs said:

Blows my mind that this topic is 7 pages long, but you mention the Allison 10spd valve body, and people are like "eh (shrug) what can ya do, eh?" 

 

Still an amazing lack of info on a $10,000 trans that locks up the rear wheels just,,, whenever. 

I have no problems with my 10 speed allison branded transmission. Nor anyone i personally know. Just internet hype. 

 

Maybe the transmission needs a catch can. 

 

Dont come to this thread,

 

 

Edited July 3, 2025 by lineman1234

[BuckWallace]

1 hour ago, lineman1234 said:

Maybe the transmission needs a catch can. 

I think you're on to something there.

[johnnyquick]

I run one and have for the last 40k miles, there is always moisture and crappy looking stuff in it whatever is I am glad it is not going in to my engine.

The best 6.2 tuners out there run them on ALL the engine that they work on,  those engines are tuned to the utmost efficiency levels.

I would put there thoughts and opinions up there pretty high for information.

I run it year round in the Pacific Northwest inland areas where it gets pretty cold and have had zero issues, I do know of a guy in Canada that DID have frozen moisture problems.

 

 

[Jettech1]

Too funny, I started this thread coming up on 3 years ago.  I've been gone from this site for almost 2 years now.  I still have my beloved 22 gasser.  35k miles on it.  Not one hiccup so far.  I will be buried in it, until my son grabs it before my funeral...lol....

 

Dale

[KARNUT]

57 minutes ago, Jettech1 said:

Too funny, I started this thread coming up on 3 years ago.  I've been gone from this site for almost 2 years now.  I still have my beloved 22 gasser.  35k miles on it.  Not one hiccup so far.  I will be buried in it, until my son grabs it before my funeral...lol....

 

Dale

Well, I was wondering where you went.

[Jettech1]

1 minute ago, KARNUT said:

Well, I was wondering where you went.

A lot happened last year.  I retired from Delta in Atlanta after 37 years of service.  Moved to mooseass Alabama so we could be closer to family.  3 miles actually...lol....grabbed a job at the end of July 24 as a regional manager for a facilities maintenance company that was contracted by the DOD, so I had 17 military sites I took care of.  Hated that job and took another one being a dayshift supervisor at Hellas in Dadeville, AL.  We make the plastic thread for a lot of football fields using astro turf.  It's been quite a ride so far but I am loving not living in Atlanta anymore.  37 years in Atlanta was 36 too many...lol.....