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Jon A

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Jon A last won the day on December 2 2016

Jon A had the most liked content!

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About Jon A

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    Senior Enthusiast

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    Everett, WA
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  • Drives
    2014 Denali 6.2 CC Standard Bed

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  1. Let us know how they work!
  2. Fuel Injectors ?

    It sounds like you're talking about replacing injectors on a typical port injected engine. This engine is direct injected. Much different deal.
  3. I disagree. What failure rate are you looking for, failure rate of what compared with what? One single AFM lifter failing and causing damage to one single engine in the fleet provides an infinitely higher failure rate than an otherwise identical engine that has no AFM lifters making that mode of failure impossible. It's like arguing the odds of cutting yourself while juggling knives is very low if you are good at it. Just one cut makes your rate of cuttage from juggling knives infinitely higher than somebody who does not attempt to juggle knives. This line of reasoning would only work if you believed that no AFM lifter had ever failed and caused damage. We all know that isn't true. That's probably because information like that would be Proprietary (or ranked higher) GM information. Anybody with access to it who released it would not only be fired for it, but held legally liable [just as it says in the Protecting Proprietary Information Agreement (or whatever GM calls it) that they likely make their employees with access to such information sign once a year]. Asking for information that is impossible to obtain is not a reasonable argument. All we can do is read the tea leaves: https://static.nhtsa.gov/odi/tsbs/2016/SB-10078567-7690.pdf Note, there is no equivalent TSB for standard lifters spontaneously failing. Note to amxGuy1970, that TSB is not for old engines. Note they acknowledge a chance this has caused the lifter to be stuck or spun in its bore. When that happens it's very likely to ruin the camshaft, and a ruined camshaft (if bad enough, if the condition existed long enough) can easily turn the engine into a large paperweight as metal filings in the oil have caused damage throughout. Note they identify the most likely cause as a failure of the locking pin in the AFM lifter. A standard lifter will never fail due to failure of the internal locking pin because standard lifters do not have internal locking pins. Standard lifters don't juggle those knives. No cuts ever for them. I think we can agree, the mere existence of this TSB is proof that this mode of failure does, in fact, happen. I agree that the failure rate data would be nice to have, it's hard to make an informed choice without it. But consumers must do that every day with virtually every product we buy. All we can do is read the tea leaves and make a choice based upon how we read the leaves and what is most important to us. For me, reliability is important. I go on 2,000 mile roadtrips with the family and spend time out in the boonies, miles from pavement where there is no cell coverage and an engine issue would mean walking back to civilization (or riding a horse if I was lucky enough to have brought one). Even the thought the damage would be covered under warranty (if lucky enough to have it happen in the next 7 months before my warranty runs out) is nice but little solace compared with the thought of the truck being stuck in some dealership 1000 miles from home for a month or two. That goes so far beyond an inconvenience, I'll do anything I can to reduce the odds of it happening. And since the speed limit across most of Montana is 80 MPH, I would not likely realize much gas savings from the system anyway, even if the truck was stock. Others, for whom saving gas may be highly important, can choose to keep the system active. And that's a reasonable choice for them. But doing so without acknowledging they are even making a choice, believing there is ZERO chance of a failure because of that choice is naive.
  4. To be clear, exactly nothing in my response had anything to do with "old generation" AFM systems. That's how the current system operates. The failures I was speaking of were only from this 2014+ section, where dozens (maybe more if you count them all) of users have needed their valvetrains to be rebuilt and more than a few have needed entire engine replaced due to failure of the AFM system. To not acknowledge the risk posed by the system, even if small, is to bury your head in the sand. It also had exactly nothing to do with "being stuck in old ways." As an Engineer, I'm a huge fan of new technology in all things mechanical. However, I believe the consumer is always better off when the changes are consumer driven, not driven by politicians (CAFE standards). If people are willing to accept the added cost and reduced durability of a particular system in order to save a little gas, they will pay for it and companies will build it. When activists (who frankly don't like cars in the first place unless they're electric) force manufacturers to incorporate these changes, whether the consumer wants them or not, whether the consumer is better off for them or not, that hurts the consumer with reduced choice and products they are less happy with (not just AFM, how about all the 3.08 geared trucks? How many people with 5.3's would love 6.2's instead, but couldn't get them because GM has to limit their numbers?). For example, I'm a huge fan of Direct Injection as it does offer an increased power potential and efficiency of gas engines. However, I'm not going to bury my head in the sand and try to argue that it was "ready for primetime" on these and many other engines--that there are no adverse consequences to the system. There simply are. I have yet to see any evidence offered by those who claim it has caused no issues in 100K+, 200K, etc, miles. Try taking your truck to a dyno at 150K and seeing how much power it's actually putting out compared with new. Then dyno it again with a set of new heads where the airflow isn't significantly reduced by carbon buildup on the valves. That would be evidence. Luckily in this case, the manufacturers are solving this issue (dual injection including port injection that helps keep the valves clean) so DI issues may not be anything to worry about anymore for future engines. But if you don't acknowledge there are issues to begin with, it's hard to also be a fan of the new technology that will solve them.
  5. There's no reason to feel that way as the system can be easily disabled--even in a way that won't affect your warranty. While it's obvious some here like the system, there's no denying the fact it is a liability. The vast, vast, majority of major mechanical issues with these engines (hard parts breaking, valvetrains and sometimes entire engines needing to be replaced) reported here can be traced back to the AFM system. No, it doesn't happen all that frequently, but the simple truth is those issues wouldn't have happened at all without it. The good news is, the anecdotal evidence (doubtful anybody has done a long term, scientifically controlled study) is strong that simply disabling the system pretty much eliminates the possibility of these issues occurring. And it makes sense from a mechanical standpoint, if you understand how the system works. The most common mode of failure is the AFM lifters themselves getting stuck in the collapsed condition. A pushrod engine with collapsed lifters will quickly destroy itself. The AFM lifters use a small secondary spring to keep them riding on the cam lobe and to keep slack out of the valvetrain when in this condition. The problem is they are way, way, too small to perform this function at anything other than low RPM. So, when one or more gets stuck in the collapsed condition, anytime you accelerate even moderately (much less tow something up a hill) where the engine requires mid-range, much less high RPM, you are driving a pushrod engine with a collapsed lifter. This will beat the valvetrain to death and possibly take the entire engine out with it if not identified and fixed immediately. That doesn't even take into account all the secondary issues that occur when the computer is trying to fire that cylinder with one of the valves not working. With the system disabled, the lifters are never "activated" to voluntarily collapse and lock themselves in that condition. If they never enter that condition, it's much more difficult for them to get stuck in that condition. Personally, I deactivated the system when my truck was nearly brand new for these reasons (I expect to keep it a long time, so long term durability is a goal). Besides, most of my long trips are 75-85 MPH with a decent load and 34-35" tires so the potential benefit of the system was going to be minimal for me. Would I feel even better physically removing these lifters and replacing them with dead-nuts reliable standard lifters (which would also allow the use of stronger valvesprings)? Yes, and I plan to do that eventually. That would give this engine the bulletproof valvetrain GM V8's used to be known for (and the current 6.0 in the HD's enjoys because it lacks this system). But it's my belief that deactivating the system so dramatically reduces the chances of having an issue with it, there's not an urgent need to do that. I'll get around to it when I eventually do a cam swap--and standard lifters allow the use of much improved cam lobes so you can have more power along with more durability.
  6. That's very normal and those temps are nothing to worry about. If you do want it to run cooler (especially if towing heavier loads is in the future) and want to see what a couple cheap mods can do to help, look at this thread:
  7. I'm sorry, I missed the fact you have airbags. How much air do you normally run in them? If you have much air in them when you aren't hauling much they will firm up the ride, there may be some improvement to be had there.
  8. Thoughts on this rig?

    Oh well, they're cheap.
  9. Thoughts on this rig?

    If you liked them on your 09, there's no reason not to. They will help when towing.
  10. With that specific use in mind a Denali probably wouldn't be my first choice. The Magnetic Ride shocks do complicate things, but the big issue is the NHT package isn't available. Specifically for RV use, especially if there's a chance of a 5th wheel in the future, the extra payload of the NHT can really be beneficial. A standard length box is also much better for that, and while they do exist on Denalis, it might be hard to find one. As for the OP's issue, I do think it's possible to remove the magnetic shocks, I think I've seen threads where people do that and use something to fool the computer but I haven't paid much attention. A good set of aftermarket shocks can provide a really good ride, there are a lot of choices out there. I'd also suggest having Deaver make you a custom spring pack for the rear, giving them your goals so they can make a set of leaf packs that will give you the ride you want.
  11. Yeah, me too. Not just for maneuvering in tight spots, but for driving offroad. Especially when cresting a hill, rise or hump, you really can't see the trail worth a damn in these trucks. The front camera would be a tremendous help.
  12. Thoughts on this rig?

    That's great they let you do that. That's obviously the best way to see how it does--see for yourself!
  13. Thoughts on this rig?

    Yeah, it'll run on lower octane, but I really wouldn't recommend it. It should get enough better mileage than your current truck fuel costs will likely be a wash. As for how it will handle your trailer, it should be an improvement over your current truck--not a night and day dramatic difference that you'd notice with a 2500, but stiffer springs and stiffer hitch should handle things a bit better. The integrated brake controller is nice, the larger rear axle adds durability, etc. The big thing, of course, is the engine and transmission and how it will maintain speed up hills with much less effort. It will feel much more capable and make towing, especially in the mountains, much more enjoyable. Another big thing you'd gain is the increased payload and rear GAWR, which will give you a lot more breathing room before the weight police come and get you. Overall, I'd say it's a worthwhile upgrade if you found a good deal. Not transformative as changing to a 2500 would be, but this truck would actually make a nicer daily driver instead of a worse one.
  14. Diamondback vs ARE topper

    Yeah, it is difficult to use the space on the sides. The cargoglide is 4' wide so you could still stack plywood on it, etc, but obviously it has to fit between the wheelwells. I'm currently using some of that space for extra gas, etc, but much is wasted. When I figure out the best way to do it, my plan is to fit the cargo boxes from either the Titan XD or the 2019 GM's to the sides. There will be some cutting involved (especially with the GM ones) if it's even possible at all, but that would make good use of that space. A couple of the totes I carry around most of the time have things like tow ropes, tire chains, ball mounts, torque wrench, etc, that would fit in side boxes like that giving me more space for cargo. I'm not sure I can pull it off, but I do want to try one of these days. On fiberglass toppers not being durable, I've never heard that either and have seen many quite old, used hard ones that are still in great shape. I know when I was shopping for mine, there were some available at less than 1/2 the price of my Snugtop, there may be a "you get what you pay for" aspect to it. On leaving the bed open and not using a topper at all, the final nail the the coffin for me was the first match I went to after buying the truck. The back seat was so stuffed with all my gear I could barely close the doors and couldn't recline my seat. Besides fear of theft, it also rained the whole drive there, and snowed the drive back. So my big, beautiful 6.5' bed was useless the entire time. That did it for me....
  15. Can I tow this?

    My understanding of the OEM anti-trailer sway system (which may not be perfect) is that it will only kick in when the stuff is about to hit the fan. An anti-sway device built into many WDH's is designed to act much sooner, hopefully preventing things from ever getting that far. So, pretend the factory system is not there--use an anti-sway device of some sort, especially with long travel trailers and hope you never have to test the factory system.

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