Ya, sure it's because of semiconductor shortages......

 

Or failed lifters?

 

Supposedly it is "temporary"

 

I think al the guys i know wiht the 5.3 have bought the thing that disengages the AMFAM

 

OR bigger picture, the environmental push for elimination of the V8 ... be careful poking fun a good V8 with minor service issues. Complaining is easy but a V8 is better off than an boosted 6 or 4 for trucks but bandwagon complaining will lead to an earlier demise.

 

True, who needs it when we will all be driving electric vehicles anyway? Could be GM sees it as a waste of time and resources.
So how is this big 'semiconductor shortage' going to effect EV production?? Oh lord.

 

My Silverado has the DFM and I have never noticed an issue. With the AFM, you can see how many cylinders you are running on, I believe. With the DFM, there is no display to show what the engine is doing.

I haven't had any issues, but I just got first oil change last week and just clicked over 7300 miles.

I agree with @oxidizr, be careful what you ask for. The V8 is on a increasingly rapid road to extinction. On the other hand, when I was walking the lot last week while my oil was changed, the handful of Silverados on the lot only included one 5.3L V8 in the bunch. Is that because they can't build them because of chip shortages, or is that because the only engine anyone wants to buy is the 5.3L V8, so they sell quickly.

@White016, surely an EV will not need any chips to run? You just plug it into that magic receptacle on the wall, it magically gets recharged, and then you go forth to spew fresh oxygen for us to breath as you drive around the countryside.

 

@White016, surely an EV will not need any chips to run? You just plug it into that magic receptacle on the wall, it magically gets recharged, and then you go forth to spew fresh oxygen for us to breath as you drive around the countryside.

Ignorance is bliss sometimes I guess....It sure doesn't help the pocketbook or even the environment in oh so many ways.
Oh well, EVs have lots of torque, that's what I'm looking forward to.

 

Just to be clear, the 5.3 itself is not being discontinued, only the AFM and DFM feature… article says “The change will go into effect this week. 5.3L engines with AFM will be built without the feature starting today, March 15th. 5.3L engines with DFM will be built without the feature on March 29th. All pickups built with either 5.3L engine after those dates will not have the fuel-saving features”

 

This is correct, but there are people who think that V8s are evil inventions that will destroy the world. They care not that these V8 trucks are a major tool in the roof over their heads and the roads under their EVs.

 

Hmm, wonder how one goes about ordering one specifically without this feature and if this means it gets regular lifters? Having owned a early 2000's gmc sierra with the former 5.3 without that feature for over 150k miles and a 2017 gmc sierra with the newer 5.3 and that feature for about 30k miles, I can attest that there was no observed mpg difference with similar configurations. That 2017 sure made odd noises at times though where the old one was trouble free.

 

Article says the RPO code is YK9, not sure about the lifters.

 

On that note. . I picked up an OBD Range AFM Disabler and have been running it on my 2017 3.6L V6.
No more V4 mode and so far can not tell any significant MPG difference. Even around town where it usually kicks in the most.

 

Great move on the AFM Disabler.

 

FWIW, I have never disabled AFM on my 2007 Sierra iron block 5.3L which has 140k miles and no issues. Before I lifted the truck it would easily get 22mpg average.

I know many do disable it, especially when they get exhaust because the 4cyl mode sounds a bit odd.

 

Reading the article, it sounds as if they are essentially doing a factory afm delete which would involve using regular roller lifters instead of the afm specific lifters. This is a nice opportunity to get a truck with an engine that should be durable for the long haul.

 

I doubt it, as in..It will be really hard to find one of these factory deleted trucks. I am almost certain they will all have gov't tags and idle around. It will be impossible to find one of these at an auction but again GM wins with selling they're platform to known buyers and moving forward to a future that many(me) aren't looking forward to. Small turbos are going to win until GM decides to release the EV, hang onto the 5.3 DFM if you like it and get ready for some resale value for those of us that like to stop for gas.

 

The lifter issue is gone as it was addressed. We used to sell a lot of upgrade kits to eliminate them but the new vehicles see little issue. The truth is most of these engines with AFM were running 95% of the time on all cylinders.

The only reason they use it is that the MFGs earn credits with the EPA that give them an advantage for mileage ratings.

These are called Off Cycle credits and are applied to fuel and emissions systems that are difficult to measure. The Government applies a credit to the technology and in many cases it is better than reality. These make the credits easy bonuses for the MFGs.

Note these credits can be AFM out also apply to glass that rejects heat, some paints that reflect heat and even low resistance alternators. They have a list of items covered and it can be wide ranging.

The only real advantage here is they will cut you and extra $50 off the truck for not having it.

The AFM system really is a Rube Goldberg deal that makes the government happy. Also it may affect emission more than MPG. We don't get those numbers but firing less cylinders for a short time is more emission than MPG friendly.

 

The lifter issue is gone as it was addressed. We used to sell a lot of upgrade kits to eliminate them but the new vehicles see little issue. The truth is most of these engines with AFM were running 95% of the time on all cylinders.

The only reason they use it is that the MFGs earn credits with the EPA that give them an advantage for mileage ratings.

These are called Off Cycle credits and are applied to fuel and emissions systems that are difficult to measure. The Government applies a credit to the technology and in many cases it is better than reality. These make the credits easy bonuses for the MFGs.

Note these credits can be AFM out also apply to glass that rejects heat, some paints that reflect heat and even low resistance alternators. They have a list of items covered and it can be wide ranging.

The only real advantage here is they will cut you and extra $50 off the truck for not having it.

The AFM system really is a Rube Goldberg deal that makes the government happy. Also it may affect emission more than MPG. We don't get those numbers but firing less cylinders for a short time is more emission than MPG friendly.

The Stop/Start technology is in the same category. I remember about 80% of the time to turn it off when I crank my Silverado. The other 20% of the time, I stop at an intersection and hear the engine stop. In most cases, I am already releasing the brake to pull away from a stop sign or right turn on red, and it starts back up, and I reach down and disengage it. There is no way the 3-4 seconds at most the engine was off and then had to go through a re-start cycle that I saved any gas or reduced emissions. If I am at a light, I will sometimes wait for the light to change or the engine to re-start on it's own to disengage the system. I like to think I may have saved a few drops of gasoline that way.

I was sitting at a stop sign once and did not realize the engine had died. When I went to pull away, the split second it took for the starter to engage the engine almost got me killed.

 

When I built a 5.3 that was originally a DOD, I used a different camshaft, lifters, valley cover, oil pump, and a few other parts, so wondering if they do a hardware change too, or only the electronics.

 

There's pretty much zero shot they're changing out the hardware. I'm sure they're just leaving the electronics disabled since they can't get the processor chip for the controller module.

 

If I want to feel torque I get into either our 03 SS Camaro or the 03 Silverado with the 6.0 gas engine. I don’t feel much torque from the 2020 Colorado that we bought last year.

 

Yeah I hear those '03 Fbodies were quite special!

 

Now the Colorado and Canyon are being shut down temporarily.
GM forced to cut production of midsize pickups due to chip shortage

 

Now the Colorado and Canyon are being shut down temporarily.
GM forced to cut production of midsize pickups due to chip shortage

Uh oh, that's not good...