Is AFM still an issue for 5.3L Chevy trucks?

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My co-worker is looking for a used Chevy Silverado. I told him from 2007 on there is an issue with their AFM systems. I know there are ways to disable or delete the AFM system. My question is, did the this issue ever get resolved, basically? If so, what year model Silverado is safe to buy with this in mind?
 
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Yes, it is.
No, it hasn't even been resolved, nor will it be.
If you don't want AFM, the 6.0l engines don't have it.

What is weird is how some trucks can go 250-300k miles with it and not have a problem but there are brand new 2019/2020 trucks destroying lifters at 1,500 miles. Even disabling AFM isn't a guaranteed fix. The only guaranteed fix is an AFM delete kit.
 

4WD

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My 2017 has 45k and is seamless + extended warranty so not going to panic over the imminent bashing
Might worry at a higher mileage if it has a gasket leak or some other reason to work on the engine …
 
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For a small fee you can shut AFM off using a tuner. IMO disabling it reduces the chance of having a problem with it. Lifters designed to collapse every few hundred feet seem like the worst idea ever when they wear a little and fail to pump back up. Keeping them pumped up all the time is just less wear and tear on that mechanism. I also like heavier oils too for positive pressure. My 17 - 6.2l hesitated between modes till it was shutoff now purrs like a kitten. Actually id be more concerned with injectors on DI engine.
 
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I have the 4.3 Sierra, 52K miles and no lifter problems. My Dad has the 2017 5.3 Silverado and tows his antique cars all over the country in an enclosed trailer, with his foot on the floor the whole way. Not sure how many miles he has on his, but no trouble there either. It did, however, kill his 2013 Silverado.
 

CKN

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My co-worker is looking for a used Chevy Silverado. I told him from 2007 on there is an issue with their AFM systems. I know there are ways to disable or delete the AFM system. My question is, did the this issue ever get resolved, basically? If so, what year model Silverado is safe to buy with this in mind?
You would be giving your friend incorrect information. In 2007 there were some issues. In late 2011 they installed a different valve cover that took care of most problems. I have had three of the 5.3's. A 2011, 2012 and a 2018.

How many have you had?

Anything manufactured from 2012 is a very safe bet. GM sells 40,000plus units a month of these trucks. The vast majority with the 5.3. Do the math....................
 
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You would be giving your friend incorrect information. In 2007 there were some issues. In late 2011 they installed a different valve cover that took care of most problems. I have had three of the 5.3's. A 2011, 2012 and a 2018.

How many have you had?

Anything manufactured from 2012 is a very safe bet. GM sells 40,000plus units a month of these trucks. The vast majority with the 5.3. Do the math....................
Well, to be fair, the new valve cover helped with oil consumption and sticky rings. It doesn't do much for the AFM lifters or the reason they fail.
 

CKN

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Well, to be fair, the new valve cover helped with oil consumption and sticky rings. It doesn't do much for the AFM lifters or the reason they fail.
Again-40,000 units a month. How many FAIL?

Do THE MATH. Hint-many, many zeros behind the decimal point.
 
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The issue needs to be divided between pre-2014, and 2014 onward AFM systems. They are totally different. The 2014 AFM system got a variable rate oil pump, redesigned lifters, larger oil pan and went to 0w20 Dexos motor oil. I guess we know the pre 2014 was a POS. We need to hear from 2014 onward owners as their vehicles rack up miles.
 
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Does the AFM make these idle a little rough without a check engine light come on? I rode in a couple of these newer than 2014 and I thought maybe it was a bad coil or something worse but didn't want to bring it to the attention of the owners.
 

4WD

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Does the AFM make these idle a little rough without a check engine light come on? I rode in a couple of these newer than 2014 and I thought maybe it was a bad coil or something worse but didn't want to bring it to the attention of the owners.
Mine has done that a couple times … just dumped in a large bottle of Techron in a half tank.
Normally it idles smooth and quiet …
 

CKN

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Does the AFM make these idle a little rough without a check engine light come on? I rode in a couple of these newer than 2014 and I thought maybe it was a bad coil or something worse but didn't want to bring it to the attention of the owners.
No. But if the throttle body gets dirty they idle like a lumber truck.
 
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Here are two screen shots with info on the 2014 and up 5.3 engine. It is a Gen V with a revised oiling system and larger capacity 8 quart oil pan. The 5.3 engine is an L-83. I believe beefing up the lubrication system and specifying Dexos oil was all part of the improvements. Enjoy.

F1A54E38-D578-4E53-8731-341824182CE0.png
308AA8A7-5F41-4249-970C-7D366EA79A6E.png
 
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gfh77665

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You would be giving your friend incorrect information. In 2007 there were some issues. In late 2011 they installed a different valve cover that took care of most problems. I have had three of the 5.3's. A 2011, 2012 and a 2018.
My information is correct. 2007 is the year the issues started, and although changes were made along the way there has not been a complete resolution of the AFM yet by GM. Taking care of "most" problems is good, but incomplete. GM has used a "bandaid" approach.

He does not want 2006 or earlier Silverado, he wants something newer, and I understand that. I agree that if he was to buy, he should get something after 2011 or even better after 2014.
 
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CKN

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My information is correct. 2007 is the year the issues started, and although changes were made along the way there has not been a complete resolution of the AFM yet by GM. Taking care of "most" problems is good, but incomplete. GM has used a "bandaid" approach.

He does not want 2006 or earlier Silverado, he wants something newer, and I understand that. I agree that if he was to buy, he should get something after 2011 or even better after 2014.
My point is based on number of units sold vs. problems it's a very, very, small percentage. AGAIN-I have has three a 2011 (later build date after new valve cover) a 2012, and a 2018. ALL problem free.
 

gfh77665

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I hear you and believe you. No one has even remotely suggested that every single unit will fail. I am glad you lucked out so far.
 
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Oil pump, Vacuum pump & Injector failures are what go wrong with the Gen V DI engines, Lifter failures are rare but do happen.

A very good customer of mine owns is a Electrical Contractor & owns a fleet of F250 service trucks....But his personal work truck is a 2015 Silverado 4x4 L83/6L80E & beats the snot out of it along with using it as a 3/4 ton pick up. Vacuum pump, Condenser, & Torque Converter have been the only non maintenance items replaced in 200,000 miles. The AFM & TCC PWM was tuned out before 40,000 miles. The Billet Cover Twin Disc Torque Converter was technically installed as a preventive measure because how hard he beats on this truck. He can burn down a set of brakes in 30,000 miles!!
 
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I have a 2013 Silverado ext cab 4x4 1500 with the 5.3. Considering tuning out the AFM, but frankly, when monitoring the engine mode, the only time it's not in 8 cyl is when I'm coasting down a hill. I've never noticed any vibration or impact of the AFM. Always use a Dexos 1 G2 oil and change out at about 25% life remaining. Am open to being convinced to tune AFM out if there is a good reason - I sure don't see it impacting mileage since I'm almost always in 8 cyl anyways.
 
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