Catch can & AFM dissble??

WilliamBos · August 6, 2016

For those that added a catch can to your AFM trucks, did you find that this rectified any oil use?

Did you also disable the AFM?

Would disabling AFM cause warranty headaches? A Diablo or Superchips is how I'd do it, would this leave a mark on the ECM even if stock tune were reinstalled before a warranty visit?

Moroso cstch can? Any other favourites?

Zachlovesfood · August 6, 2016

A tune will definitely hurt your warranty. GM is known to be a stickler about that.

Sent from my iPhone using Tapatalk

dorkweed · August 9, 2016

I put just the "basic" Elite catch can on my truck with 300 miles on the clock. Most of my driving is around suburbia at speeds under 55mph, so I use M5 to lock out AFM. For long highway jaunts; when I want all 6 gears, I bought the "Range" AFM delete module................which I used this past weekend on a 600+ mile round trip. Worked flawlessly. I only plug it in when I'm gonna need it.............otherwise it's in the box in the center consul.

Silverado-Hareek · August 11, 2016

In theory, a catch can won't rectify oil consumption. The oil in the PCV gases will either burn off in the combustion chamber without a catch can or get trapped in the catch can. Either way you're losing oil between oil changes. It's a minor amount....maybe 4-8 oz between changes but it's still being lost.

Now if these engines develop the oil consumption problem related to the AFM system, disabling AFM has been known to solve that issue. But nothing can stop oil blow by getting into the crankcase and leaving the engine permanently through the PCV system.

Rkaroll953 · August 11, 2016

well i have the range device in 24/7 and a catch can. i deffinetly dont get the amount of oil that i see on here that people share but i do get oil. in like 2k miles i can get maybe 2-3 oz? its to the point where i dont have to worry about cheking it that often and also i have never seen oil in the intake tube.

** also i bought a UPR billet catch can. its made in america and billet aluminum. fits mint on my fender bracket and has a mesh and a baffle and it was just over 100$. would deffinetly recomend it.

Silverado-Hareek · August 11, 2016

The amount of oil you're catching is mostly related to the quality of the oil catch can that you have. The volume of water in the catch can that is trapped is related to the climate. In the winter I'll drain 6-7 ounces of fluid (oil and water together) every 500 miles. In the summer, I'l drain 2-3 ounces fluid (mostly oil) every 2,000 miles or so. In both instances, the rate of oil caught in the catch can remains relatively constant, but the rate of water caught fluctuates.

Cowpie · August 13, 2016

A catch can won't rectify a oil consumption problem, but could reveal where the oil is being consumed. On my previous 2013 1500 5.3L and my current 2015 2500 6.0L, I installed catch cans on both of them. The amount of oil the engine "consumed" almost mirrored exactly what the catch can captured. Both pickups have about a 1/4 qt consumption between oil changes, and that is almost precisely what the catch can captures. Maybe only a couple of oz difference.

On my 2006 Cadillac CTS 3.6L with 55,000 miles on it, same thing only worse. The engine "uses" about 1/4 qt per 1000 miles. That catch can captures about 4-5 oz in that time frame, so the engine is only "using" about 3 oz of oil in that time frame. The 3.6L is a notorious oil burner, but in fact the PCV port is poorly designed with no effective baffling. So a lot of oil gets drawn up thru the PCV. This is something that has affected the entire GM lineup. They have gotten a better hold of the problem on some engines now. In my experience, the brand of oil had little effect on consumption either way.

mookdoc6 · August 15, 2016

I agree with the 3.6 totally I had exact same oil usage never a problem with engine. The new 5.3L with 0W-20 after thousands of miles it would have to consume oil it's just to thin not too? Since I am new to catch can I always wondered how it would effect oil consumption. Thanks!

Cowpie · August 15, 2016

The 20w is not too "thin", but if I had one of the pickups that recommended a 20w, I would use a 5w20 over a 0w20. Just my comfort level. A 5w20 would have a lower NOACK (burn off vaporization rate) than a 0w20. Primarily because a 5w20 takes less viscosity modifiers to get the cold flow spread. And viscosity modifiers are what break down over time due to heat and shearing forces. And a 5w20 would work for just about every climate except northern Canada and Alaska. Both a 0w20 and a 5w20 have the same exact viscosity at operating temperatures. Only the cold start flow rating is different.

Keep in mind, viscosity is not "thickness", it is resistance to flow. You want an oil that has a certain amount of flow resistance so that it is not pressed out of bearings and such too quickly, yet, a low enough viscosity so that it actually gets into the bearings and such quick enough in the first place. A balancing act if there ever was one.

dorkweed · August 15, 2016

Just over 2300 miles on the truck in my signature in 1 month since I bought her. I can count the miles on, "one hand", that this truck has been in V-4 mode. My oil level hasn't changed at all since took ownership. I've emptied my catch can 4 times so far............just to get a baseline of what to expect...................and I've not gotten more than about an ounce. It seems real "watery" to me also..................0W20 oil????? I dunno; because I'm coming over from driving Dodge/Cummins for 18 years straight.........and it was 15W40 in them for me!!!

It has been HOT and HUMID here in "The Peoples Republik of Illinoiz" though since I've had this truck.

Silverado-Hareek · August 15, 2016

Just over 2300 miles on the truck in my signature in 1 month since I bought her. I can count the miles on, "one hand", that this truck has been in V-4 mode. My oil level hasn't changed at all since took ownership. I've emptied my catch can 4 times so far............just to get a baseline of what to expect...................and I've not gotten more than about an ounce. It seems real "watery" to me also..................0W20 oil????? I dunno; because I'm coming over from driving Dodge/Cummins for 18 years straight.........and it was 15W40 in them for me!!!

It has been HOT and HUMID here in "The Peoples Republik of Illinoiz" though since I've had this truck.

So you've drained about 1 oz in 2300 miles?

dorkweed · August 15, 2016

So you've drained about 1 oz in 2300 miles?

Less than 1oz. each time I drained the catch can. Re-read my post, and I wasn't very clear on that, sorry.

So; probably less than 4oz total so far.

Seems quite watery...................but I've not dealt with 0w20 oil at all. Looks like oil though. Some condensate maybe???

Oil on the dipstick is the same as when bought.

Just saying!!

Silverado-Hareek · August 15, 2016

Less than 1oz. each time I drained the catch can. Re-read my post, and I wasn't very clear on that, sorry.

So; probably less than 4oz total so far.

Seems quite watery...................but I've not dealt with 0w20 oil at all. Looks like oil though. Some condensate maybe???

Oil on the dipstick is the same as when bought.

Just saying!!

4oz of oil in 2300 miles is about right. 0W-20 by nature is very watery. The fluid you're draining likely looks really dark right now which is basically just dirty oil.

In the winter time, you will need to drain it every 500-700 miles and you'll have about 4-6 oz of a fluid mixture in that time frame that will be mostly water with some oil mixed in. The rate of oil that your catch can catches remains relatively constant. It's the water content that increases in the winter. The winter drain will not be as dark....it will look kind of like coffee with a lot of cream in it....a very light brown mixture of oil and water. If you let it sit for a while, the oil will eventually float to the top of the water and you can see the difference in the oil versus water quantities.

Cowpie · August 23, 2016

Yeah, a lot of condensation capture in winter time. I have to really stay on top of my catch cans during winter months.

ata3001 · August 24, 2016

Aren't these new motors just great. Now we need to drain off oil using catch cans we never used to have to do on motors that typically ran hundreds of thousands of miles. Kind of like how the "NEW" math is so much better than "OLD" math.