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The 3.6L engine in your 2012 Impala doesn't have AFM (thankfully!) - apparently, it caused all sorts of oil consumption issues and really didn't make that big of a gas mileage difference anyway....
 

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If there is a slight grade like our airport entrance, the first time I had been there in years, before all of the 9-11 security, where you quickly need to figure what lane you need to get to various areas, I found that my Impala would roll right back up to 50+ MPH after I had slowed down to 30 MPH, (with no one behind me) and I never had to ride the brakes with any other car under a similar situation. I had just bought my LTZ, and it quickly taught me a lesson, I will remember. Third gear solves that problem too. Being in 3 cylinder mode might have something to do with how easily it keeps its speed up on a slight down grade? (I could do without AFM) If it wasn't necessary to pull the engine to change the cam, I would consider installing the kit myself, depending on what it costs, of course.
 

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Ah, I missed the .6vs.9 lol.

the wifes denali has it over time it kills the valve train, and they are made of gold, like $900 ish for the 4 that shut down vs $29.99 for stock or something like that.. Most people just delete it after warranty and swap the valve spings and stuff.
 

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can I deactivate with out a cam swap?

I have the TSB on the cam & lifter kit but the way I read it is that it's to be used if you need a cam or lifters.

It states: "Condition

Some customers with the 3.9L AFM engine (RPO LZ8 or LZG) may experience a condition that requires the camshaft and/or lifters to be replaced.

Cause

The AFM lifter is no longer being manufactured and the engine has to be converted to a non AFM engine"

It goes on to describe the contents of the kit which includes a cam. I don't need a cam my engine ingested a valve seat and I have it out and apart to replace a piston & head. I want to deactivate the AFM wile I'm at it but the kit is pricy. Can I just replace the 6 AFM lifters, install the blocking plate and get the VIC# so my dealer can reprogram the ECM?
 

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i always wondered why GM stopped using AFM in the 3.9, i liked the idea.
 

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I wonder if the cam in the 3.9L with AFM has different specs then the cam in the non AFM 3.9L engines, I've heard the AFM lifters can't handle vary aggressive cam profiles. Maybe the replacement cam is revised to maximize fuel economy without taking into consideration what the AFM lifters can handle?
 

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Oil consumption here is still about 3,000 miles per quart. The AFM system still works fine, although I would suggest the AFM concept is better suited for an 8-cylinder, as mine is always blipping in and out at the 70mph speed limit - mostly defeated by either adding 5mph to stay mostly in 6-cylinder mode, or slowing by 5mph for more time in 3-cylinder mode. I do notice a 1-2mpg boost in the instantaneous mpg when in 3-cyl mode over 6-cyl mode.
Did notice when the oil pressure switch failed - it stayed in 6-cylinder mode all the time - perhaps an easy way to defeat AFM is to just unplug this switch, then put a piece of black tape over the MIL indicator for the nuisance factor. After all, if one does lose oil pressure, not really going to need a warning light to let you know somethings up. :)
 

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Ah, I missed the .6vs.9 lol.

the wifes denali has it over time it kills the valve train, and they are made of gold, like $900 ish for the 4 that shut down vs $29.99 for stock or something like that.. Most people just delete it after warranty and swap the valve spings and stuff.
How did you determine that, "Most people just delete it after warranty and swap the valve springs and stuff."?
 

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I wonder if the cam in the 3.9L with AFM has different specs then the cam in the non AFM 3.9L engines, I've heard the AFM lifters can't handle vary aggressive cam profiles. Maybe the replacement cam is revised to maximize fuel economy without taking into consideration what the AFM lifters can handle?


There is a difference for sure with the DoD cam, I can tell by the tuning specs between 06/09-11 3900s and 07-08 3900s. Most DoD cams have specific lobe designs on the DoD cylinders. That said, most DoD lifters seem to work fine on regular cams given a reasonable max lobe lift, but GM definitely had durability of the lifters in mind.


Also worth noting that the 70mph hard to keep in DoD comment is identical on most V8s, so in that respect the DoD in the V6 worked just and only as well as the V8 counterparts.
 

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I had a 3.9 2007 I just traded in on a 3.6 2012. I never noticed it burning oil,But only had 70,000. The one thing I always noticed though was a vibration between the 40-45 mph mark. It felt like it was coming from between the motor and trans.? Anyways I love the 2012 3.6 engine as it a lot smoother.
 

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Wilbur, you where told that because 07 and 08 impala's with the 3.9L had the cylinder shut off and variable upper intake. If you went with a 09+ 3.9L it won't have those options and you'd have to have your ECM retuned because of that, personally I feel it would be more worth it to install an 09+ 3.9L or a 3.5L and be retuned.

This post was about GM not offering the AFM lifters anymore, if you picked up another 07/08 3.9L and you got a bad lifter you'd have to pay to get it configured over to a 09+ 3.9L so I'd think it would be better to just pick up the non AFM 3.9L to begin with. If what I and Will think about the cams between the AFM and non AFM engines being different then converting over to the non set up would definitely require a cam install that comes in the GM kit, that would require your engine to be removed to install.
 

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I think my questions were just answred here but can someone please confirm for me....

I have a 2007 w/3900 and AFM. Well I am having the troubles involved in this thread. The car has 230k on the clock so it would be in my best interest to just swap in a low mileage engine rather than fix my high mileage just to have it toss a rod in a month.

I have located a 2006 3.9 without the AFM with 78k on the clock for $400. Am I correct in assuming I can swap in this engine and just haul it to the dealer and that can program the ECM to run this engine?

Thanks.
 

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I think my questions were just answred here but can someone please confirm for me....

I have a 2007 w/3900 and AFM. Well I am having the troubles involved in this thread. The car has 230k on the clock so it would be in my best interest to just swap in a low mileage engine rather than fix my high mileage just to have it toss a rod in a month.

I have located a 2006 3.9 without the AFM with 78k on the clock for $400. Am I correct in assuming I can swap in this engine and just haul it to the dealer and that can program the ECM to run this engine?

Thanks.
it sounds like a fun project. but these cars are cheap and plentiful. i would just get another car. after $400 you will still have a car with 230k miles on the trans and no resale value

i love these cars. being desposable and easy to replace is one reason i like them
 

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Unfortunately I just bought this one and I am in it for the long haul. The car has been immaculately cared for its entire life. There is not one spec of rust on it, not even a scuff in the paint. Just has high miles.

I make my living breathing new life into other peoples outcasts so an engine swap on an impala is not really even what I would consider a project. I just want to be sure I can swap in a non AFM engine before I lay down the cash and put forth the effort only to haul it to the dealer and they cant reprogram the computer.
 

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My '07 Impala has 318,xxx miles on its 3.9. I'd like to turn off the AFM cylinder deactivation so that it stays in 6-cylinder mode.

Is there a known way to accomplish that? (The supercharger on my other car came with a DiabloSport tuner. Will that help?)
 
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