09 Silverado HYBRID.. Disable DOD w/ HP Tuners.

Its back together and running great with a Set of Mellings brand lifters. IDK about disabling the DOD yet, as I don't feel like doing anymore with it today. Maybe tomorrow.

That's usually the brand I use as well.

Ahh, yeah both of those are clearly cheap Chinese trash. That explains a lot, look at reviews before you buy next time. The first one has zero actual good reviews. The only 3 reviews at time of this post are 1 star the second one is a mix but mostly bad reviews. Expect to pay at least $35per AFM lifter. Most will run above $45 for a decent one. On the cheap end expect to pay double what you did.

I got two different brands from Amazon.

KOAUTO Compatible with 8PCS DOD... https://www.amazon.com/dp/B08762QWXC?ref=ppx_pop_mob_ap_share

And

LC Valve Lifters Lash Adjusters... https://www.amazon.com/dp/B07W8LVWR5?ref=ppx_pop_mob_ap_share

Yikes, you got one of the junk lifters I warned about in one of my videos. I remember asking folks to let me know if they get them where they got them from. So I have to ask, where did you get the lifters and what brand?

Well, if its warped or not, I'm not going to worry about it because it was fine before the lifter failed... NOW I just have bad luck and can't get anything to go right. Initially the failure was on the intake lifter on #7... Once I replaced all the lifters on that bank I had an issue of no oil through the pushrod on #1 Exhaust... I pulled it back apart and replaced the lifter again, and HAVE A NEW PROBLEM!!! lol. This newest lifter won't lock, so it collapses just like the bad one from #7... So it has to come apart AGAIN... I'm ready to drive this truck off a bridge, but it doesn't run well enough to get me there..

When BAD LUCK hits me, it HITS ME!!!

Right I get that it runs smoothly. A bent or bad valve won't make it smoke unless it's extremely bad and causing it not to fire. With that said, these valves (intake mostly) come off the manufacturing plant with a warp to them. So if you think it runs smooth now wait till you have one with a good valve job done. Also, having straight valves does more then increase ability to idle smooth and even across all cylinders, it also increases life and reduces risk of breaking a valve. Even though they are slightly bent they will likely still seal fine but they will also have to straighten out in order to seal. This means ever time it opens it goes to factory bend then when it closes it goes to wherever the seat was ground to. This small back and forth bend will fatigue and weaken the stem over a long period of time. If the steel was not of the best quality it will lead to a dropped valve and thus severe engine damage. I get it though, not everyone wants to put the little extra into there vehicle. I have everything I do machined because I have seen and done it at the machine shop myself. I know first hand how crude some manufacturing can be to (intentionally as far as I'm concerned) make it last as close to warranty as possible.

I ran it for about 20mins, and went for about 2 miles drive, plus revved it from idle to 3,000rpm in the drive way for about 1min, going from idle to 3k then back and repeat. at about 1500rpm all the others had oil coming out, but his one. I'm curious to know why you would think the valves are warped? Until that one AFM lifter failed, this was a smooth running engine that didn't burn oil or smoke at all. (which it didn't smoke once back together either). It only has about 140k on it, so still young by my normal engine life standards. I normally get around 300k+ from 5.3l motors with the most ever being 427K when the trans blew again. I wasn't going to throw a new trans in with those miles on the motor.. Now be it, they were all LM7's but aside from the AFM I don't think there was too much changed for the Gen4's. With this being a 6.0l its not exactly the same, but also with this being a hybrid, the engine doesn't even run when driving under light load and under 30mph so that 140k miles is even less on the engine itself.

No, I wouldn't assume. These are known for not pushing much oil out of the lifters. Many times these engines need to be revved up to see oil come out. In fact I've seen when they leak a bunch of oil at idle, they are actually bad. Now if the rocker was still dry when you pulled it apart after all the running you did with it then I would be suspect and replace it. Be sure to replace the head bolts since they are tq to yield. I would seriously recommend going through the head as well but your call. The valves may seal with spring pressure on them but I guarantee they are warped.

I didn't do anything with the head, because I didn't have any issues with the head. I only had the one AFM lifter fail, so replacing them was my main goal. I also listened with a stethoscope and without seeing oil out of the pushrod, I'm guessing it was this one... I'm not 100% sure. I pulled it back out, and I don't see anything that looks off. I couldn't blow air though it in the truck, but one i got it out, I was able to.. Now to be fair, It did seem like it cleared a blockage, but thats hard to tell.

I'm going to build a tool that allows you to install lifters and pump oil through them before installation... I'm just wondering now if i should put it back together and pray, or replace the suspect lifter again just cuz... Would you assume that was the problem lifter, without seeing oil come out of the pushrod while the engine is running?

Well I assume you had the head gone through then if you worked on lots of engines. These are known for bent intake valves from factory. With that said if a valve job was done poorly and the machinist cut a bunch off the stem without cutting much from the seat or face, it could drop the stem height a considerable amount. Also the milling of the head can effect this some to. If it wasn't milled but stem was ground a bunch it could effect the ability for the cushion in lifter to be at max extension. When you pull the rocker loose, do it at bottom of camshaft lobe and pay close attention to it. If you notice the pushrod go up when you loosen it then the lifter still has room. This will tell you a lot of information on what could be happening.

I didn't have lifter tap on this Cylinder until after I replaced the Lifters. These are brand new lifters now, and I have lifter tap on 1 of the new ones. If the pushrod or rocker was worn, it would've happened before I changed the lifters. I have one more trick up my sleeve, that I've used several times before on older Lifters that would've pump up... I put a hose over the pushrod, fill it with 50w oil, then before it runs out the bottom of the pushrod, use air to for it into the lifter. I've had success getting a lifter to pump up using this in the past on older Small Blocks. Maybe it'll work on this one. I'm hoping that its just stuck at the bottom and needs to pump up some and then will start working. I also know on older engines that if i loosened some of the rockers, that it would help the lifter pump up by running it, then tighten them back down.. Maybe that'll work on this too.. I'll try that and see what happens... Then I can try to disable the AFM in HP Tuners. I'll update along the way for anyone else who reads this and runs into something else...

FYI, this is my 1st time working on an LSX engine... I've worked on 100's of old Small Blocks and 100's of other engines over the years. But this is my 1st time having an LSx Enging apart...

No, it's usually not slop in the lifter. If you have lash then you have something else to be concerned about. The pushrod and rocker could be badly worn out for an example.

Have you ever pulled a rocker and sanded / ground a few thousandths off the bottom and retorqued it to see if you could stop a lifter from chattering?

Try a little oil stabilizer and drive it if you don't find you missed a rocker. These engines struggle to get oil to the rockers at low rpm. Little drive time might take care of it. I suggest the stabilizer because it may help get the lifter to work better and once working normal oil my still sound fine.

Just a side comment. It was WAY easier to adjust the lifters with just torque, but I must say.. Full Floating lifters, (like in the old Small Blocks) is kinda nice to solve this issue. I could just find the bad one, and give it a 1/4 turn or so..

Nevermind. That hole is plugged on the back of the hybrid intake. But NEW problem. I replaced all the AFM lifters on the side that was bad, just put it back together and one of my lifters is ticking like crazy.. Even with fresh clean 5w30 and running for 20mins it still clicks so its apparently not pumping up. it runs fine, but just makes noise. Is there something im missing with these lifters that I need to do? I'm going to pull the valve cover back off and retorque all the rockers but I did them all at 22lbs when on the low side of the cam, so they should be good.

Probably just my BAD luck... One of the new lifters is bad. Oil PSIs are showing around 60psi at idle, and 80psi when i rev the engine up now... The 40psi before must have been because the little filter under the sensor was clogged completely...

Only thing for back of intake I'm aware of is for a brake booster. Not having that are you thinking of the pcv hose that goes from top of intake to the valve cover?

Ive a question... So Mine does not have a vacuum brake booster. I'm reinstalling the intake now, and i can't find any lines to connect behind the intake. I could've sworn there was a vacuum line or PCV line (one of the plastic ones) that went to the rear of the intake on the drivers side. Do you happen to know what goes there? Its basically the last thing i'm stuck on before finishing and attempting to program the ECU to remove AFM.

Thanks

Interesting, looks a lot different then hptuners I'm used to but perhaps I need to update. You are in the same tab however and all I do is disabled it. But it does appear it's opposite day if that's the stock tune. Makes me wonder if you can actually write it? I wouldn't change anything other then enable it to disable it. Never know what else is opposite. Then try to write it but be aware, you may brick the ECM for all I know. Should be interesting. Hopefully you can do it and everyone who told me otherwise is wrong. I've had lots of request for this and would love to have a possible solution.

Just an update. I'm running the most recent version of HPTuners and used the BETA version. I was able to pull the tune off my 09 Silverado Hybrid. I'm attaching 2 screenshots. One of the "STOCK" config and one of the "MODDED" config I just did. Apparently "Disabled" is actually DOD enabled, and "Enabled" is DOD DISABLED... I should be able to stop the DOD by RPM, Throttle Position, Trans Gear or one of the other options listed in the config.. Take a look and let me know what you think. Im not sure what HYST stands for tho. lol Image with Orange / yellow / red, is modded.. Thanks

The system needs 30psi minimum (26psi per spec but I like to have a little safety room). If you did actually have 40psi minimum, you likely have a blown out valley cover gasket or the bolts are loose. As for the tune thing, I just don't think any manufacturer want to deal with hybrids. I'm not sure. I just know you can't get the access to be able to tune then per the tuner box companies. I'm sure there is some smart guy hacker or something that could do it but who knows. Just get factory replacement lifters. I would recommend doing all lifters on the bank you are doing. That means both AFM and standard lifters. 4 of each. If you did just the failed lifter it should be a ht2303.

What lifters would I need for this motor? LSM 6.0L hybrid. To replace the factory ones? HT2303? Also, what is the part number for a replacement VLOM?

Thanks

How much pressure needs to be there? I know the gauges are the most accurate, but this engine always ran 40psi or better. (Until hybrid mode when the engine shuts off and then oil pressure drops the zero of course)..

And not to beat a dead horse, I'm just really trying to wrap my head around this.. it's that the software doesn't give the option to disable on a hybrid? Is that what you're saying?

Thanks for all your help.

I'm not sure why hptuners and others won't allow tuning the hybrids. It may have something to do with the integration of the hybrid system in the ECM. Yeah, the older valley accessed lifters was nice but replacing them wouldn't solve the issue for very long. Like I said earlier, they fail from lack of oil pressure during activation. So if that is not fixed it will happen again and again.

I also just wanted to add, HOW STUPID GM was for covering the lifter bores and burying them inside the block like that. Imagine how simple of a fix this would be, if it was taking place on an old Gen1 or Gen 2 style Small Block, with the exposed lifter galley right under the intake manifold. When I used to build 383's out of 350 4 bolt blocks one of the things i would do after grinding rod bolt clearances into the block was go up into the galley and smooth out the high spots, and round all the holes so the oil would flow back to the lower end quicker, and not hang around in the upper end of the engine where it wasn't needed. I had a buddy of mine with a 350 in a special application where he couldn't use a high volume pan, and kept running the 6 or 7 quart pan he had dry, and would have to back down. I ground one of the 350 2bolts i had laying around for him to try it in his application, and sure enough with that simple amount of grinding oil made its way back to the pump fast enough he never had problems sucking it dry again. After showing him exactly what mods i did, he started do it to all his builds from that point forward. Back to my point. I just wish you could still the lifers in the lifter galley. It would SOOO much easier to free a stuck on, or even replace one. AH, The good old days...

You won't be able to turn off the AFM in the tune being it's a hybrid. The VLOM mod is like a insurance policy in case the VLOM not functioning correctly is what caused the problem in the first place. I have a video explaining this https://youtu.be/xFr8TxgxJow for a bit more details. With the hybrid you will have to fix it by replacement of the lifter/s. You will also need to find the source of what allowed the lifter to have low oil pressure during activation or oil pressure when it shouldn't at the AFM side (top oil tower) of the lifter in the first place. It could be a simple plugged screen under the oil sensor or a bad camshaft bearing among other things. Good luck on your endeavors, hopefully this explanation helps.