Jump to content

Question about afm

Pgrecs

Recommended Posts

Pgrecs Enthusiast

Pgrecs

Posted
Posted

Have a 2013 5.3L Sierra SLT with afm still on and about 210k km. I’ve been reading a lot about disabling afm and all and how it drinks oil and spark plugs get coated in some nasty soot. So today I did my spark plugs to see if there was any build up. Cause they were done about 10 months ago or longer (i think).

 

when I checked the old spark plugs 1 through 8 they all looked fairly the same and had absolutely no soot build up of any kind and my oil doesn’t seem to be burning. 

 

So my question is. Should I still disable afm? Since I bought the truck 3 years ago now I haven’t had any issues (must have been built on a wedensday lol). Should I not chance it and just do it? Or leave the can of worms un opened

MaverickZ71 Senior Enthusiast

MaverickZ71

Posted
Posted
On 3/18/2019 at 10:54 PM, Pgrecs said:

Have a 2013 5.3L Sierra SLT with afm still on and about 210k km. I’ve been reading a lot about disabling afm and all and how it drinks oil and spark plugs get coated in some nasty soot. So today I did my spark plugs to see if there was any build up. Cause they were done about 10 months ago or longer (i think).

 

when I checked the old spark plugs 1 through 8 they all looked fairly the same and had absolutely no soot build up of any kind and my oil doesn’t seem to be burning. 

 

So my question is. Should I still disable afm? Since I bought the truck 3 years ago now I haven’t had any issues (must have been built on a wedensday lol). Should I not chance it and just do it? Or leave the can of worms un opened

If I were you, I'd get a Range V8 module and plug it into your OBD2 port to turn off AFM, for cheap insurance.  And you can remove the Range V8 module for dealer service.  You may notice better response and shifting with AFM turned off, and many of us noticed little to no change in fuel economy by turning off AFM.  Even if you have been lucky enough to not experience the infamous AFM oil usage problem, you may still experience AFM lifter failure and/or a pitted camshaft.  Most of the 2007-2013 GM 1500 folks on here say to turn off AFM as soon as you can.  You may also want to install an oil catch can into your PCV system.  But ultimately that is all up to you, of course.  At the very least, be sure to use Dexos-rated engine oil and change the oil and filter at the intervals specified by your Oil Life Indicator on your Driver Info Center, if not sooner.  

Pgrecs Enthusiast

Pgrecs

Posted
  • Author
Posted
26 minutes ago, MaverickZ71 said:

If I were you, I'd get a Range V8 module and plug it into your OBD2 port to turn off AFM, for cheap insurance.  And you can remove the Range V8 module for dealer service.  You may notice better response and shifting with AFM turned off, and many of us noticed little to no change in fuel economy by turning off AFM.  Even if you have been lucky enough to not experience the infamous AFM oil usage problem, you may still experience AFM lifter failure and/or a pitted camshaft.  Most of the 2007-2013 GM 1500 folks on here say to turn off AFM as soon as you can.  You may also want to install an oil catch can into your PCV system.  But ultimately that is all up to you, of course.  At the very least, be sure to use Dexos-rated engine oil and change the oil and filter at the intervals specified by your Oil Life Indicator on your Driver Info Center, if not sooner.  

Yea I use Ams oil synthetic. Very good oil I hear so that’s what I use and I usually 90% of the time change it every “50%” of the oil indicator. If everyone says don’t risk it then my all means I’m all for saving future $$$$$ even if it costs me a little now. 

Mikebtte Enthusiast

Mikebtte

Posted
Posted
1 hour ago, MaverickZ71 said:

If I were you, I'd get a Range V8 module and plug it into your OBD2 port to turn off AFM, for cheap insurance.  And you can remove the Range V8 module for dealer service.  You may notice better response and shifting with AFM turned off, and many of us noticed little to no change in fuel economy by turning off AFM.  Even if you have been lucky enough to not experience the infamous AFM oil usage problem, you may still experience AFM lifter failure and/or a pitted camshaft.  Most of the 2007-2013 GM 1500 folks on here say to turn off AFM as soon as you can.  You may also want to install an oil catch can into your PCV system.  But ultimately that is all up to you, of course.  At the very least, be sure to use Dexos-rated engine oil and change the oil and filter at the intervals specified by your Oil Life Indicator on your Driver Info Center, if not sooner.  

I second this opinion. While many people have ran the same year of model many miles with no issue, many have had issues and they get very expensive when the issue happens. It would be good insurance to disable the system while your top end is still in good shape. This will make for a long and happy relationship between you and your truck.

As mentioned, its ultimately up to you.

swathdiver Senior Enthusiast

swathdiver

Posted
Posted

Dirty oil and poor filtration is AFMs worst enemy.  In 2011 the AFM components were updated and are far more reliable than they were in the earlier years.  That being said, reliability can be increased by turning it off.  The Gen IV motors didn't make enough horsepower and torque per cylinder to get AFM running more than 10% usually, most of the vehicles were just too heavy for it.  Another 5-8 horsepower and torque per cylinder brings AFMs duty cycle up to about 50% across nearly all platforms.

  • 1 month later...
Gooseslayer717 Enthusiast

Gooseslayer717

Posted
Posted
On 3/21/2019 at 12:22 PM, swathdiver said:

Dirty oil and poor filtration is AFMs worst enemy.  In 2011 the AFM components were updated and are far more reliable than they were in the earlier years.  That being said, reliability can be increased by turning it off.  The Gen IV motors didn't make enough horsepower and torque per cylinder to get AFM running more than 10% usually, most of the vehicles were just too heavy for it.  Another 5-8 horsepower and torque per cylinder brings AFMs duty cycle up to about 50% across nearly all platforms.

I recently (2 weeks ago) Purchased a 2011 sierra SLE with the 5.3l. do ALL 2011+ have the updates? or is there a certain Serial Number that indicates if it has the updates?
Own a ram before this so new to GM but excited about building it up.

Looking to get Diablo Tuner, then upgrade with LT Headers and exhaust system.

Still learning the site so if there are any general (To-Know) forum or post please direct me in the right way.

Already looked into removing Wheel Well liner and rear lights to clean out any dirt.

 

MaverickZ71 Senior Enthusiast

MaverickZ71

Posted
Posted

I recently (2 weeks ago) Purchased a 2011 sierra SLE with the 5.3l. do ALL 2011+ have the updates? or is there a certain Serial Number that indicates if it has the updates?
Own a ram before this so new to GM but excited about building it up.

 

***********************************

 

I think the date(s) for the factory installation of the new valve cover with the revised PCV orifice and the oil deflector in the oilpan are buried somewhere in all of the posts on the "Does your GMT900 use oil?" survey posted on this forum.  I want to say the valve cover came out in mid-2010 and the oilpan deflector was a 2011 deal, but I'm not absolutely sure.  A dealer can tell you if you have the new valve cover or not by taking it off and looking at the part number.  The valve cover seemed to do more people more good than the oilpan deflector.  If you're worried about AFM problems, or already have oil usage, the main thing is to make sure the AFM function is turned off, and to use Dexos-rated engine oil.  

swathdiver Senior Enthusiast

swathdiver

Posted
Posted
5 hours ago, Gooseslayer717 said:

I recently (2 weeks ago) Purchased a 2011 sierra SLE with the 5.3l. do ALL 2011+ have the updates? or is there a certain Serial Number that indicates if it has the updates?
Own a ram before this so new to GM but excited about building it up.

Looking to get Diablo Tuner, then upgrade with LT Headers and exhaust system.

Still learning the site so if there are any general (To-Know) forum or post please direct me in the right way.

Already looked into removing Wheel Well liner and rear lights to clean out any dirt.

 

 

April was the final update if memory serves.

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
On ‎3‎/‎18‎/‎2019 at 10:54 PM, Pgrecs said:

Have a 2013 5.3L Sierra SLT with afm still on and about 210k km. I’ve been reading a lot about disabling afm and all and how it drinks oil and spark plugs get coated in some nasty soot. So today I did my spark plugs to see if there was any build up. Cause they were done about 10 months ago or longer (i think).

 

when I checked the old spark plugs 1 through 8 they all looked fairly the same and had absolutely no soot build up of any kind and my oil doesn’t seem to be burning. 

 

So my question is. Should I still disable afm? Since I bought the truck 3 years ago now I haven’t had any issues (must have been built on a wedensday lol). Should I not chance it and just do it? Or leave the can of worms un opened

You've been reading about a problem but haven't had a problem and are worried you might get the problem because some have had a problem. Read that three times slowly and ask if think a plethora of opinion will  provide any clarity.

 

Let me be clearer:

 

I've read people have flat tires...should I take the tires off my car and ride on rims?  

MaverickZ71 Senior Enthusiast

MaverickZ71

Posted
Posted
18 hours ago, Grumpy Bear said:

You've been reading about a problem but haven't had a problem and are worried you might get the problem because some have had a problem. Read that three times slowly and ask if think a plethora of opinion will  provide any clarity.

 

Let me be clearer:

 

I've read people have flat tires...should I take the tires off my car and ride on rims?  

To quote my GM service manager: "There are 2 kinds of vehicles, those that already have AFM problems, and those that will."  He drives a Toyota, by the way.  And his Tech that works on my truck drives a Honda.  Even though they could get massive GM discounts on new vehicles.  Guess that should maybe tell me something.  

swathdiver Senior Enthusiast

swathdiver

Posted
Posted
2 hours ago, MaverickZ71 said:

To quote my GM service manager: "There are 2 kinds of vehicles, those that already have AFM problems, and those that will."  He drives a Toyota, by the way.  And his Tech that works on my truck drives a Honda.  Even though they could get massive GM discounts on new vehicles.  Guess that should maybe tell me something.  

Yeah, they should go work for Honda and Toyota!  

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
4 hours ago, MaverickZ71 said:

To quote my GM service manager: "There are 2 kinds of vehicles, those that already have AFM problems, and those that will."  He drives a Toyota, by the way.  And his Tech that works on my truck drives a Honda.  Even though they could get massive GM discounts on new vehicles.  Guess that should maybe tell me something.  

And eventually bearings will wear out and so will rings and guides and seals and...and...and...and 

 

Honda has DOD in the J series engines. Toyota is working on variable compression. Soon your mechanics will be pedaling bicycles. 

KARNUT Senior Enthusiast

KARNUT

Posted
Posted
And eventually bearings will wear out and so will rings and guides and seals and...and...and...and 
 
Honda has DOD in the J series engines. Toyota is working on variable compression. Soon your mechanics will be pedaling bicycles. 

I understand people thinking on hydraulic lifters. This being the next step. The only problem is all the other products bought to the dance, such as an external vacuum pump etc. Some people see no change in fuel mileage. Some people ( under 60 mph) drivers see some gains. Then there’s the people who like tuned exhaust on V-8s. By the way my father in law just traded in a well car for Honda with the cylinder deactivation. 100K miles started using oil and running bad. I really hope yours does well.


Sent from my iPhone using Tapatalk
Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

My particular Honda does not have the J motor but does have VVT/VVL and has 222,000 miles on the clock. It's fine. Uses no oil in 7,500 on OCI.  I was just point out that we are going to get more of what we don't want before we get nothing at all. 

 

The truck has 89,500 as of today so 4,500 on this OCI. Used none so far. Erie quite. AFM seamless and on allot. Ran home from Oglesby Ill today at 62 mpg (100 kph) into and out of the Illinois River Valley hill country and clocked 30.4 mpg for the trip. Slight tail wind. 7 - 10 mph. 72 F air temp and right at 204 F on oil and 145 F on the trans. I'm having a hard time finding flaws in my ice cream.....so far....LOL. 

 

Dad use to say they run the best just before they BLOW!! 

 

Oil pressure has always been a concern with this motor. Not use to the low pressures they design them to these days. That worries more than the AFM, GDI or the VVT.

 

Ya know what? Time will tell.

 

It can or it can't, it will or it wont. 

MaverickZ71 Senior Enthusiast

MaverickZ71

Posted
Posted
On 5/14/2019 at 9:09 PM, Grumpy Bear said:

My particular Honda does not have the J motor but does have VVT/VVL and has 222,000 miles on the clock. It's fine. Uses no oil in 7,500 on OCI.  I was just point out that we are going to get more of what we don't want before we get nothing at all. 

 

The truck has 89,500 as of today so 4,500 on this OCI. Used none so far. Erie quite. AFM seamless and on allot. Ran home from Oglesby Ill today at 62 mpg (100 kph) into and out of the Illinois River Valley hill country and clocked 30.4 mpg for the trip. Slight tail wind. 7 - 10 mph. 72 F air temp and right at 204 F on oil and 145 F on the trans. I'm having a hard time finding flaws in my ice cream.....so far....LOL. 

 

Dad use to say they run the best just before they BLOW!! 

 

Oil pressure has always been a concern with this motor. Not use to the low pressures they design them to these days. That worries more than the AFM, GDI or the VVT.

 

Ya know what? Time will tell.

 

It can or it can't, it will or it wont. 

It is what it is.  Unless it ain't.  

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Deadwood
      primary drive belt tensioner

      By Deadwood · Posted

      I bought belts and pulleys for my '20 L5P at Rock Auto a couple years ago. I have used them for many years, and almost always save significant money, especially when I buy maintenance stuff ahead of time.   They carry many OEM parts, which is all I use unless an aftermarket is shown to be same/superior, or if it is an insignificant part or unavailable OEM part anywhere else. RA is usually lower priced, often by a bunch, but parts are sometimes unavailable or out of stock, and I do shop around and sometimes find better prices at other sites.   Be aware that you pay shipping, and if you buy multiple items and they are coming from different warehouses, the shipping can kill the advantage. Planning ahead is best if possible.   If you have a transmission service in the near future, check out their OEM (AC Delco ULV) fluid, usually MUCH less than anywhere else.
    • Deadwood
      10L1000 anyone with High Mileage ? I hate Damocles....

      By Deadwood · Posted

      New member here, very long time occasional guest. Saw this thread, thought it would be a good time to contribute someting. It is only my experience and not a claim that everyone will have the same.   I bought my '20 3500 L5P new and have put 99.9% (literally) of it's current ~400k miles on it myself, with over 50% of that towing loads between 4k to 15k, and to me this truck has been nothing short of amazing. For the first 235k I had zero issues, and from there until 321k I replaced a NOx sensor, two failing glow plugs, and three of the notorious injector connectors. I believe this truck is in part, a testament to good luck, but also good care and following a decent maintenance schedule (I also keep meticulous records.) As a result, it looks as good as a well cared for 70k rig, up and down, inside and out.   At some point before that 321k mile mark I began to get a little spooked about the 10L1000, especially the valve body. Word of mouth about potential issues prompted me to jump on the net to sift through all the noise and determine what all the fuss was about. I routinely take long trips, coast-to-coast and points in between, so roadside breakdowns can be '...a thousand miles from nowhere' and a bit of a challenge, and though I had no issues, my guard was up and activated.   And then I stumbled across a chance to salvage some parts off a new 2025 that had been wrecked in transport. I grabbed a few wear items (alternator, pulleys, etc.) and on a whim asked what the ten speeder would cost me. It was cheap...really cheap. I knew some changes had been made in the '24+ version 10L and were supposedly not compatible, but I called service/parts at my local Chevy dealer and asked why and they didn't know. A call to a well known aftermarket transmission outfit revealed it was very likely it would be fine, but to them not 100% sure.   Because it was cheap (really cheap) and I was spooked, I took the chance. Had it installed by a local shop and it worked like a champ, shifted just like the original. At it's first service at 37k, I had the shop put in a Next Gen valve body kit, which after some initial hiccups and rough shifts, smoothed out though with somewhat firmer shifting.   All that said, I have a very serious concern about my newer transmission as just two weeks ago it suddenly began to exhibit a strong reluctance to engage forward or reverse. It was a bit past due anyway so I took it in for service. The reason it was sticking was due to 'glitter' in the fluid clogging the filter...not good folks, often indicates a converter giving out. We ended up going ahead with the new filter and fluid, first to see if it would move and shift, and then if so buy me a little time. It did, and I've driven it over a thousand miles and it is shifting smooth, no noises or slipping. Regardless, it looks like a third gearbox is in my future so I can resume taking long trips with some confidence. In the very short term, my curiosity will have me examining the fluid to check how much glitter has reappeared.   An earlier poster had alleged, in the context of 10L100 failures, that it is another example of how we seasoned citizens somehow descend into hysteria, lose control of our senses, and react irrationally after brief encounters with the idiocy of the internet infosphere. Let me say (and I have used and abused said internet since it's infancy) there is no segment of the populace that has a corner on over-reaction to digital garbage. Just as my offering of experience in this arena is purely anecdotal and should not be considered gospel or all-encompassing, I believe it is still worthwhile information to consider, along with other relevant anecdotal experiences about things like complex transmissions, especially when balanced with other sources.   So to answer the original question, yes I got high miles out of my first 10L, trouble free for 321,000. Now I really wonder how much longer it would have went. Did I 'overreact' to the internet ghouls by replacing a 'good' one with a 'bad' one? Maybe. Who knows, the thing might have taken a puke a 100 miles later. So I'll just fix it again, then move on and start thinking about all the other stuff that will eventually wear out. It still has the original brakes (they're at ~60%), original injectors/pump, turbo, water pump, etc....pretty much original everything. Knock on wood.
    • swathdiver
      6 Speed vs 8 Speed

      By swathdiver · Posted

      At peak temperature.  They get to cool down and warm up more, especially those with the external cooler.  I have three GMT900s and one of them has over 225K on its original transmission.  Fluid gets changed about every 36K miles, all of it.     It's not the bean counters, it was the government.  They had to meet CAFE standards and other government requirements.   To get around that, we tune them and modify them to our liking.
    • GMCustomerService
      Will not stay in Reverse

      By GMCustomerService · Posted

      Our customers' safety isn't something we take lightly. To ensure you get the proper assistance for your truck's repairs, please fill out the form at https://s.chevy.com/support-request with all pertinent details including your username.
    • GMCustomerService
      2026 Z71 Forward and Rear Park Assist help

      By GMCustomerService · Posted

      We appreciate you sharing your experience with your truck. To ensure we get you the proper assistance, please fill out the form at https://s.chevy.com/support-request with all pertinent details including your username.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...