Magnalfow **** and tips

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swathdiver

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What’s up guys just wanted to share what I did to my suburban couple of days ago. I was looking at the corsa exhaust but when I saw the price I was like whoa. So I took it to my local muffler shop and had a magnaflow **** and tips put on. And this is the end result. I have a video but it’s not good sound so I’ll post up a cold start tomorrow of the sound View attachment 184237View attachment 184238

Florida?
 

Boatguy272

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Excuse my ignorance,,,,, why/how can AFM hurt the engine.

And is there the same issue on the 6.2 10 Speed trans?

Thanks !!!
 

iamdub

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Excuse my ignorance,,,,, why/how can AFM hurt the engine.

And is there the same issue on the 6.2 10 Speed trans?

Thanks !!!

Mostly it's when the AFM lifters fail. The AFM lifters in the current generation of engine (LT) are much improved over those in the '07-'14. There are updated lifters for that generation, as well and they may all be the same.

There are other failures associated with the AFM system such as excess oil consumption. AFM works by bleeding off oil from the 8 AFM lifters to allow them to collapse. When AFM disengages, the oil is pumped back into them. Without getting too technical, the dickering around with the oil stuff created more oil mist in the engine's crankcase. This oily air gets routed back into the engine's intake to be sucked into the cylinders and burned off. The oil gunking up the intake and crudding up the piston rings in the cylinders leads to big problems.

It seems that, for the most part, GM has the lifter design and the oil consumption handled on the current generation. But, there still are failures.

AFM has nothing to do with the transmission other than you being able to keep AFM from engaging by holding your transmission in a lower gear.
 

Boatguy272

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Thank you !! at $80,000 I need this truck to last a VERY long time so anything I can do to prolong its life I will do.
 

dbbd1

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Mostly it's when the AFM lifters fail. The AFM lifters in the current generation of engine (LT) are much improved over those in the '07-'14. There are updated lifters for that generation, as well and they may all be the same.

There are other failures associated with the AFM system such as excess oil consumption. AFM works by bleeding off oil from the 8 AFM lifters to allow them to collapse. When AFM disengages, the oil is pumped back into them. Without getting too technical, the dickering around with the oil stuff created more oil mist in the engine's crankcase. This oily air gets routed back into the engine's intake to be sucked into the cylinders and burned off. The oil gunking up the intake and crudding up the piston rings in the cylinders leads to big problems.

It seems that, for the most part, GM has the lifter design and the oil consumption handled on the current generation. But, there still are failures.

AFM has nothing to do with the transmission other than you being able to keep AFM from engaging by holding your transmission in a lower gear.


Nice and concise, thanks!
 

iamdub

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Thank you !! at $80,000 I need this truck to last a VERY long time so anything I can do to prolong its life I will do.

The best you can/should do is regular oil changes with a top-quality filter and synthetic oil to keep the small passages and valves in the system from getting clogged and/or inoperable. I go by the oil's appearance rather than the mileage since I'm replacing the oil to get the contaminants out more so than because the oil is "spent" and has lost it's protective properties. For me, this is around 5,000 miles which conveniently is a great mileage to rotate the tires so it's all one big routine 5K-mile service. Also, regularly check your oil level to monitor consumption. I'd install a catch can at least as an additional monitoring point. Pretty much all of them work the same way, so there's no real reason to buy a $300 one over an $80 one. I think mine was around $70 when I bought it through a group purchase years ago (I have this one). Adding a stainless scrubber pad to it will make it catch more oil.

Going a step further, you can disable the AFM system either by getting a custom tune ($100+ and will void your warranty) or with the Range device that plugs into the OBD port. The Range won't void your warranty and can simply be unplugged if your truck needs warranty service. There's the method where you put your trans in manual mode and select a gear lower than one of the OD gears. I don't know what gear(s) this would be in a 10-speed. This keeps AFM from engaging so you lose the fuel economy benefits (if any). But you further decrease economy because you're driving around at higher RPM.

The idea of disabling AFM is to keep the lifters from constantly bleeding down and pumping up as they do when the system is operating. They stay pumped up just like the other eight lifters in the engine or like the hydraulic lifters in any modern, non-AFM/DOD-type engine. Theoretically, this should drastically prolong the life of the lifters and other relevant components.

The ultimate step is to DELETE the system by removing the AFM components and replacing them with their non-AFM counterparts. Of course, this is much more expensive and involved and will void your warranty.

On such a new vehicle with the "latest and greatest" parts and a warranty, I'd (1) maintain it impeccably and (2) leave it alone or disable it with the Range device.

My experience with AFM is that it doesn't return anywhere near the fuel economy to outweigh the risk. But, I have a lesser powerful and lesser efficient motor (MPFI instead of DPFI being the biggest and best difference) with a 4-speed trans. Also, the benefit of AFM is hugely dependent upon the type of driving that is done. For mine to be even worth considering keeping, I'd have to drive at speeds under ~60 MPH with no accelerations or stops, no inclines, minimal turn radiuses and no headwinds for about 80% of every drive I make. I don't live immediately off of a desolate highway somewhere in North Dakota with all of my destinations being immediately off of that same highway.
 

PG01

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The best you can/should do is regular oil changes with a top-quality filter and synthetic oil to keep the small passages and valves in the system from getting clogged and/or inoperable. I go by the oil's appearance rather than the mileage since I'm replacing the oil to get the contaminants out more so than because the oil is "spent" and has lost it's protective properties. For me, this is around 5,000 miles which conveniently is a great mileage to rotate the tires so it's all one big routine 5K-mile service. Also, regularly check your oil level to monitor consumption. I'd install a catch can at least as an additional monitoring point. Pretty much all of them work the same way, so there's no real reason to buy a $300 one over an $80 one. I think mine was around $70 when I bought it through a group purchase years ago (I have this one). Adding a stainless scrubber pad to it will make it catch more oil.

Going a step further, you can disable the AFM system either by getting a custom tune ($100+ and will void your warranty) or with the Range device that plugs into the OBD port. The Range won't void your warranty and can simply be unplugged if your truck needs warranty service. There's the method where you put your trans in manual mode and select a gear lower than one of the OD gears. I don't know what gear(s) this would be in a 10-speed. This keeps AFM from engaging so you lose the fuel economy benefits (if any). But you further decrease economy because you're driving around at higher RPM.

The idea of disabling AFM is to keep the lifters from constantly bleeding down and pumping up as they do when the system is operating. They stay pumped up just like the other eight lifters in the engine or like the hydraulic lifters in any modern, non-AFM/DOD-type engine. Theoretically, this should drastically prolong the life of the lifters and other relevant components.

The ultimate step is to DELETE the system by removing the AFM components and replacing them with their non-AFM counterparts. Of course, this is much more expensive and involved and will void your warranty.

On such a new vehicle with the "latest and greatest" parts and a warranty, I'd (1) maintain it impeccably and (2) leave it alone or disable it with the Range device.

My experience with AFM is that it doesn't return anywhere near the fuel economy to outweigh the risk. But, I have a lesser powerful and lesser efficient motor (MPFI instead of DPFI being the biggest and best difference) with a 4-speed trans. Also, the benefit of AFM is hugely dependent upon the type of driving that is done. For mine to be even worth considering keeping, I'd have to drive at speeds under ~60 MPH with no accelerations or stops, no inclines, minimal turn radiuses and no headwinds for about 80% of every drive I make. I don't live immediately off of a desolate highway somewhere in North Dakota with all of my destinations being immediately off of that same highway.
You don’t?
 

iamdub

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You don’t?

I live in a very rural area where I can go 45-55 MPH for about 3 miles at a time at most. Once I get to the main highway, I have to accelerate hard in the short merge lanes to reach the flow of traffic as everyone (including cops) are going 15-20MPH over the posted speed limit of 65. Then, it's about 10 miles of ~75 MPH with sudden slamming of brakes to avoid getting sideswiped by someone swerving into my lane without warning as they pass someone on the right. After that 10 mile stretch of a CF, we merge onto I-10. For that, the merge lane is actually a deceleration lane because that part of I-10 is a horrendous bottleneck from another main highway exiting and entering into it followed by a long and steep bridge that kills semis daily followed by a surprise exit halfway down the other side followed by a blind turn where another interstate merges onto it with a surprise ended lane just as you come out of that blind turn. In Louisiana, we drive on I-10 mostly with one pedal- the brake. We get on 10 and idle in gear, letting off every few seconds or so until it's our turn to get through the blind/surprise turn.

So, no, AFM was rarely engaged before I had it disabled. It was a hindrance for me cuz it cost me valuable milliseconds in acceleration windows.

Thank you for prompting me to vent.
 

PG01

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I live in a very rural area where I can go 45-55 MPH for about 3 miles at a time at most. Once I get to the main highway, I have to accelerate hard in the short merge lanes to reach the flow of traffic as everyone (including cops) are going 15-20MPH over the posted speed limit of 65. Then, it's about 10 miles of ~75 MPH with sudden slamming of brakes to avoid getting sideswiped by someone swerving into my lane without warning as they pass someone on the right. After that 10 mile stretch of a CF, we merge onto I-10. For that, the merge lane is actually a deceleration lane because that part of I-10 is a horrendous bottleneck from another main highway exiting and entering into it followed by a long and steep bridge that kills semis daily followed by a surprise exit halfway down the other side followed by a blind turn where another interstate merges onto it with a surprise ended lane just as you come out of that blind turn. In Louisiana, we drive on I-10 mostly with one pedal- the brake. We get on 10 and idle in gear, letting off every few seconds or so until it's our turn to get through the blind/surprise turn.

So, no, AFM was rarely engaged before I had it disabled. It was a hindrance for me cuz it cost me valuable milliseconds in acceleration windows.

Thank you for prompting me to vent.
Live in N. Dakota?
 
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