Unsure if I want Tahoe with AFM

[iamdub]

Oh - Not knocking what you said. Not at all. Just trying to give you some props man. I am not a big fan of AFM either, just haven't gotten to the point that I want to dig into it on our 2013 yet. That whole DOD crap back in the day was a joke as well, for sure.

I didn't take it as a knock and I appreciate the props, even more so the Pulp Fiction reference. I was really just trying to say that I didn't blindly decide that AFM was crap because that was the popular opinion. I tested it with my own vehicle and compared to many others. Fair is fair- AFM blows.

 

[Just Fishing]

I went with the popular decision, AFM sucks.

I never really had an issue other than a lifter tick here and there.
Final straw was when my oil pump started acting up, i decided this would be the last time i fk with the damn oil pan.
"While I'm in there" and did a full delete.
I can tune it a bit my self, so it was an "easy" delete for me.

I also found i had an exhaust leak (apparently)... broken exhaust bolt in the head.
Worst possible location if the heads were installed.

While I'm in there...




Oh and i can totally peg my oil pressure gauge @ 5k rpm.

 

[Larryjb]

I didn't take it as a knock and I appreciate the props, even more so the Pulp Fiction reference. I was really just trying to say that I didn't blindly decide that AFM was crap because that was the popular opinion. I tested it with my own vehicle and compared to many others. Fair is fair- AFM blows.

Actually, Ecoboost blows, quite literally in many ways.

So, I wonder if DFM will fare better than AFM? It's relatively new to GM, so any problems won't have cropped up yet, or are just cropping up now I'm sure.

Most of you know how to delete AFM, and have done so using several approaches, but I assume that physically converting back to conventional lifters is the best approach. If DFM turns out to be not so great, can it be removed as easily? If so, at least you can delete it if you get AFM or DFM. If you have a newer Ford, you're stuck with Ecoboost. Deleting it leaves you with a Bennett Buggy. (There's a great piece of Canadian history we can be a little proud of, sort of.)

 

[wjburken]

Actually, Ecoboost blows, quite literally in many ways.

So, I wonder if DFM will fare better than AFM? It's relatively new to GM, so any problems won't have cropped up yet, or are just cropping up now I'm sure.

Most of you know how to delete AFM, and have done so using several approaches, but I assume that physically converting back to conventional lifters is the best approach. If DFM turns out to be not so great, can it be removed as easily? If so, at least you can delete it if you get AFM or DFM. If you have a newer Ford, you're stuck with Ecoboost. Deleting it leaves you with a Bennett Buggy. (There's a great piece of Canadian history we can be a little proud of, sort of.)

I have a 2016 F150 with the 3.5L EcoBoost and other than not getting the superduper fuel economy, I have been very happy with it. They made some definite improvements around 2012 or 2013 and the 2nd gen EcoBoosts are much more reliable. I get what you're saying though. I can choose to delete AFM from my 2013 Denali and still have a 6.2L motor with the same horsepower. If I take the EcoBoost out of my F150, I am left with a pooch of a 3.5L.

 

[iamdub]

Actually, Ecoboost blows, quite literally in many ways.

So, I wonder if DFM will fare better than AFM? It's relatively new to GM, so any problems won't have cropped up yet, or are just cropping up now I'm sure.

Most of you know how to delete AFM, and have done so using several approaches, but I assume that physically converting back to conventional lifters is the best approach. If DFM turns out to be not so great, can it be removed as easily? If so, at least you can delete it if you get AFM or DFM. If you have a newer Ford, you're stuck with Ecoboost. Deleting it leaves you with a Bennett Buggy. (There's a great piece of Canadian history we can be a little proud of, sort of.)

I look at it like buying a first year of a new car model- you just don't. The AFM in the '08-'09 or '10 GMT900 is the "first year model"(let's call it "AFM v.1"). Yes, they improved its primary components in the later years (we'll call that "AFM v.2"), but it's still the first rendition. I'd bet that DFM is a further improvement over AFM v.2 then doubled since it works on all eight cylinders. So, I wouldn't call it "new", just multiplied. But, it's still collapsible lifters controlled by a VLOM. I don't know al the fine details of the DFM system, but I bet it can be deleted just the same. Actually, I bet it can be deleted while keeping the DFM cam since all the cylinders, lifters and cam lobes are the same.

 

[Larryjb]

This is as much as I know about the differences between AFM and DFM. It uses switching lifters like AFM, except there are 8 instead of 4, so this part is multiplied as Chris stated.

My knowledge is very fuzzy regarding the oil control, and this part of DFM seems different because it eliminates the Lifter Oil Management Assembly.

https://gm-techlink.com/?p=11880

Will eliminating the LOMA make the system more reliable? I have no clue. I'd say that frequent oil changes with synthetic oil are important, but I'd say that for almost any modern engine now.

 

[wsteele]

This is as much as I know about the differences between AFM and DFM. It uses switching lifters like AFM, except there are 8 instead of 4, so this part is multiplied as Chris stated.

My knowledge is very fuzzy regarding the oil control, and this part of DFM seems different because it eliminates the Lifter Oil Management Assembly.

https://gm-techlink.com/?p=11880

Will eliminating the LOMA make the system more reliable? I have no clue. I'd say that frequent oil changes with synthetic oil are important, but I'd say that for almost any modern engine now.

Thanks for the link, very interesting.

 

[iamdub]

This is as much as I know about the differences between AFM and DFM. It uses switching lifters like AFM, except there are 8 instead of 4, so this part is multiplied as Chris stated.

My knowledge is very fuzzy regarding the oil control, and this part of DFM seems different because it eliminates the Lifter Oil Management Assembly.

https://gm-techlink.com/?p=11880

Will eliminating the LOMA make the system more reliable? I have no clue. I'd say that frequent oil changes with synthetic oil are important, but I'd say that for almost any modern engine now.

Cool! I misread the tech article (or maybe I didn't and it was incorrect?), but it was a couple years ago so I can't recall nor find it now. I think the valves in the block would be a more reliable design. At least their operation is faster and more precise.

 

[wsteele]

I was talking to the service advisor I always use when I have the local dealer work on my Yukon (2007). He is a great guy. I called him about another thing, but when I was talking to him, I asked him if they ever did lifter swap outs on higher mileage, earlier model year AFM engines as a preventative measure. He said, "no, as long as the engine is maintained, the lifters should be fine. As long as it is quiet and you maintain it, just drive it."