GM Bulletin on aftermarket air intakes

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hagar

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My transmission began shifting softer after the Y-pipe and cats were replaced. Gas mileage has improved but shifting still soft several months later. Been too wet to datalog for a BlackBear update to the tune.

He surely did your first remote tune with the underlying problem. All you have is the information available to you at the time. A new log and it will be spot on.
 

Tylus

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Just got off the phone with GM and they confirmed any aftermarket part, even theirs, will void the warranty if anything happens. Just a fyi
so, it was mentioned earlier in this thread. but you need to read up on the magnuson-moss act.

say I install a leveling kit on my Burb. 2 weeks later the trans blows out. GM will be required to honor any/all warranties.

same situation, but this time a CV boot tears on the front axle (instead of trans failure). GM can reasonably deny coverage. Because the aftermarket component directly caused the failure.

That in essence is what the magnuson-moss act states. You can modify your vehicle. If a failure occurs, GM must prove that your modification caused the issue.


So in the case of this thread, a CAI can cause issues due to dirt, and over-oiling. Otherwise, it can't damage the vehicle. So again, if say an injector went out and washed a cylinder, GM could not deny warranty claims due to the CAI. It wouldn't hold in court and they know it. But if the MAF went bad (oily), or debris got into a cylinder...that would be a direct consequence of the CAI



All bets are off if you do custom tuning. You are pretty much guaranteed to lose if you do custom tuning and there is a motor/trans warranty claim. Too easy to tie correlations.
 

hagar

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so, it was mentioned earlier in this thread. but you need to read up on the magnuson-moss act.

say I install a leveling kit on my Burb. 2 weeks later the trans blows out. GM will be required to honor any/all warranties.

same situation, but this time a CV boot tears on the front axle (instead of trans failure). GM can reasonably deny coverage. Because the aftermarket component directly caused the failure.

That in essence is what the magnuson-moss act states. You can modify your vehicle. If a failure occurs, GM must prove that your modification caused the issue.


So in the case of this thread, a CAI can cause issues due to dirt, and over-oiling. Otherwise, it can't damage the vehicle. So again, if say an injector went out and washed a cylinder, GM could not deny warranty claims due to the CAI. It wouldn't hold in court and they know it. But if the MAF went bad (oily), or debris got into a cylinder...that would be a direct consequence of the CAI



All bets are off if you do custom tuning. You are pretty much guaranteed to lose if you do custom tuning and there is a motor/trans warranty claim. Too easy to tie correlations.
so, it was mentioned earlier in this thread. but you need to read up on the magnuson-moss act.

say I install a leveling kit on my Burb. 2 weeks later the trans blows out. GM will be required to honor any/all warranties.

same situation, but this time a CV boot tears on the front axle (instead of trans failure). GM can reasonably deny coverage. Because the aftermarket component directly caused the failure.

That in essence is what the magnuson-moss act states. You can modify your vehicle. If a failure occurs, GM must prove that your modification caused the issue.


So in the case of this thread, a CAI can cause issues due to dirt, and over-oiling. Otherwise, it can't damage the vehicle. So again, if say an injector went out and washed a cylinder, GM could not deny warranty claims due to the CAI. It wouldn't hold in court and they know it. But if the MAF went bad (oily), or debris got into a cylinder...that would be a direct consequence of the CAI



All bets are off if you do custom tuning. You are pretty much guaranteed to lose if you do custom tuning and there is a motor/trans warranty claim. Too easy to tie correlations.
 

hagar

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In this case the air intake is just as much to blame as the lift is for causing tie rod angles. The transmission in his truck relies on the accurate and factory calibrated air flow to control how the transmission works. Change the air flow of the air intake system on the new gm 6 and 8 speed trannys, and it directly affects the transmission.
 

hagar

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In this case the air intake is just as much to blame as the lift is for causing tie rod angles. The transmission in his truck relies on the accurate and factory calibrated air flow to control how the transmission works. Change the air flow of the air intake system on the new gm 6 and 8 speed trannys, and it directly affects the transmission.

Man I suck at using quotes on this site!! Lol 95 percent of the "tuners" that have hacked their way through life in the past don't know how to tune these new gm trannys because they have no idea how they work. It is NOT the same way they used to work, and oil or not causing maf contamination, I can actually blow your tranny up by changing air flow and never touch the tranny tables. I am with gm on this one.
 

hagar

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If you don't understand how it works you won't understand why it works. All of the shift pressures and such use torque based calculations largely based off the measured air flows and such on these newer trannys. If I mess up the calculated air flow into the engine on a new 6 speed or 8 speed it messes up the pressures and timing of the transmission. It 100 percent is NOT a magnuson act claim.
 

Tylus

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In this case the air intake is just as much to blame as the lift is for causing tie rod angles. The transmission in his truck relies on the accurate and factory calibrated air flow to control how the transmission works. Change the air flow of the air intake system on the new gm 6 and 8 speed trannys, and it directly affects the transmission.
Unless he has an air leak after the MAF, there is zero unmetered air getting into the motor. Biggest issue he'll see with a CAI is that more air can flow vs the factory airbox. But the MAF can still meter the volume of air. It's just a matter of the PCM being able to adjust to the increased volume...or it's too limited in the tables and cannot adapt.

I'm surprised it's not throwing a CEL. but didn't he say it's tuned?
 

hagar

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Unless he has an air leak after the MAF, there is zero unmetered air getting into the motor. Biggest issue he'll see with a CAI is that more air can flow vs the factory airbox. But the MAF can still meter the volume of air. It's just a matter of the PCM being able to adjust to the increased volume...or it's too limited in the tables and cannot adapt.

I'm surprised it's not throwing a CEL. but didn't he say it's tuned?

You are thinking in the way the processors were before the last couple of years. If you change the air flow without compensating for it in the tune it can cause tranny shifting problems. It doesn't have to be an air leak, it is simply the truck thinking it is in a different state than it actually is, and it changed the way the transmission functions. If you have ten percent more air at 2 thousand rpms at a given load point, the transmission shifts like it would thinking the truck is running stock. It doesn't know the air flow has increased, the transmission shifts and pressures based off set points. You need t changed the information the computer thinks is normal to make the tranny shift normal. I am sure most intake manufactures have had to battle a bolt on intake for that reason. Some might not have it nailed down, while others do. And it is also a lot easier to screw up vehicle by vehicle now. If I add 5 percent to the maf transfer on a 2017 silverado, the tranny shifts like garbage. It's not the same anymore
 

Tylus

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Makes sense. Wonder how hard tuning the new 10 speed that Ford/GM created is? I quit running CAI's a while back. Realized they are junk unless you're actually running a hot tune with full bolt-ons. Even then, most stock air-boxes can outflow any air demands the motor needs for a NA application.

I actually ran a stock airbox with my RoushCharger vice the CAI/Elbow. Absolutely hate those oil filters.

CAI does make the motor sound better though. About all good for
 
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daves09

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Unless he has an air leak after the MAF, there is zero unmetered air getting into the motor. Biggest issue he'll see with a CAI is that more air can flow vs the factory airbox. But the MAF can still meter the volume of air. It's just a matter of the PCM being able to adjust to the increased volume...or it's too limited in the tables and cannot adapt.

I'm surprised it's not throwing a CEL. but didn't he say it's tuned?
No time. Just the
You are thinking in the way the processors were before the last couple of years. If you change the air flow without compensating for it in the tune it can cause tranny shifting problems. It doesn't have to be an air leak, it is simply the truck thinking it is in a different state than it actually is, and it changed the way the transmission functions. If you have ten percent more air at 2 thousand rpms at a given load point, the transmission shifts like it would thinking the truck is running stock. It doesn't know the air flow has increased, the transmission shifts and pressures based off set points. You need t changed the information the computer thinks is normal to make the tranny shift normal. I am sure most intake manufactures have had to battle a bolt on intake for that reason. Some might not have it nailed down, while others do. And it is also a lot easier to screw up vehicle by vehicle now. If I add 5 percent to the maf transfer on a 2017 silverado, the tranny shifts like garbage. It's not the same anymore
It doesn' have a tune. Just a high flow muffler and exhaust resonator delete. And yes the maf was reading 13 at start up, which it should read 6 or 7. So almost double the ppm. I did call SLP and give them the scenarios but the saud there engineers did testing on this cai. But they did get bought out by Roush. I even called K&N and asked about a oiless filter. So my suggestion after all this is to leave the new 17 and newer vehicles stock. I agree to much computer timing things unless you truly do a total tune like Hennessey.
 

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