Both of my vehicles have cylinder deactivation. The Honda 3.5L and the GMC 5.3L. I have been reading around the forums and while both motors seem to be fairly reliable, they both have had their share of issues related to the Cylinder Management mode. Correct me if I am wrong but from what I have read, when in this mode it seems that the cylinders that arent firing run hotter than the other cylinders and tend to be more prone to piston carbon baking. If this is the case, then in theory would an oil like Pennzoil Ultra that tends to have the lowest NOACK numbers be best for these engines?
Cylinder Deactivation Fuel Management
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Any high quality full synthetic oil at a reasonable interval should help mitigate these issues from occurring. Synthetics are able to better deal with heat and are more resistant to oxidation.
The cylinders that AREN'T firing run hotter? Not likely. What is more likely is that the non-firing cylinders accumulate a residue of oil that gets kinda cooked by repeated, rapid compression cycles inside a cylinder that does remain hot from recent use (and the repeated compressions) and tends to gum the rings.
Yes, I think uber-low NOACK numbers would help that issue. Low NOACK oil should be able to tolerate the environment in an unused (but still hot) cylinder better than a high-NOACK oil.
Yes, I think uber-low NOACK numbers would help that issue. Low NOACK oil should be able to tolerate the environment in an unused (but still hot) cylinder better than a high-NOACK oil.
I agree, these "dead" cylinders should get cool really quick from the pumping actions of the cylinder with no fire. Carbon would be a major concern. Don't these MDS systems alternate cylinders rapidly to alleviate this issue?
^ It depends on the engine design. Volkswagen's new BlueMotion Concept car at the Detroit Auto Show, for instance, will be doing cylinder deactivation on a straight 4-cylinder engine, with the two inside cylinders deactivating. There are also 6-cylinder engines that rotate which cylinder is deactivated.
The bottom-line is these engines are designed for cylinder deactivation. Excessive engine wear should not be of concern, especially if you are using a quality synthetic as you propose.
The bottom-line is these engines are designed for cylinder deactivation. Excessive engine wear should not be of concern, especially if you are using a quality synthetic as you propose.
IIRC not all of these engines use a rotating cylinder deactivation system, which was probably one of the reasons Honda had issues with some of their V6 engines employing cylinder deactivation. I'd bet a rotating cylinder deactivated engine will have less problems than one that shuts the same cylinders down all the time. Even so I think a quality synthetic oil would be a wise choice.
For my Honda I just run a quality synthetic like PP, M1 or Edge and change out every 6 months. The oil seems to get dirty much faster than a regular engine, but have not seen any signs of sludge or other issues related to cylinder deactivation.
The honda system uses the same 3 cylinders. I thought it was determined that "side" that has the problem is the one that is running all the time?
Originally Posted By: Miller88
I thought it was determined that "side" that has the problem is the one that is running all the time?
Nope, other way around I believe. Looks to be 1,2 and 3 cylinders. Link:
http://www.driveaccord.net/forums/showthread.php?t=141065&highlight=cylinder+deactivation
The guy in the 2nd post is a Honda tech. This thread also(post #5):
http://www.driveaccord.net/forums/showthread.php?p=1340385&highlight=vcm#post1340385
I thought it was determined that "side" that has the problem is the one that is running all the time?
Nope, other way around I believe. Looks to be 1,2 and 3 cylinders. Link:
http://www.driveaccord.net/forums/showthread.php?t=141065&highlight=cylinder+deactivation
The guy in the 2nd post is a Honda tech. This thread also(post #5):
http://www.driveaccord.net/forums/showthread.php?p=1340385&highlight=vcm#post1340385
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Many here forget that Chrysler has been using a cylinder deactivation system on the 5.7's since 2004 IIRC.
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
MolaKule
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I have a 5.3L V8 TrailBlazer and the same 4 cylinders are shut down for economic cruise and low power.
I would prefer a "rotating shudown" sequence of cylinder deactivation but my engine rebuilder says it has more to do with engine balancing, and the EC software would have to be more complex.
Interesting discussing.
I would prefer a "rotating shudown" sequence of cylinder deactivation but my engine rebuilder says it has more to do with engine balancing, and the EC software would have to be more complex.
Interesting discussing.
Originally Posted By: SteveSRT8
Many here forget that Chrysler has been using a cylinder deactivation system on the 5.7's since 2004 IIRC.
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
Other than a funny sounding exhaust, apparently, theirs works pretty well.
Many here forget that Chrysler has been using a cylinder deactivation system on the 5.7's since 2004 IIRC.
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
Other than a funny sounding exhaust, apparently, theirs works pretty well.
Originally Posted By: Miller88
Originally Posted By: SteveSRT8
Many here forget that Chrysler has been using a cylinder deactivation system on the 5.7's since 2004 IIRC.
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
Other than a funny sounding exhaust, apparently, theirs works pretty well.
Which is pretty amazing for Chrysler electronics...
Originally Posted By: SteveSRT8
Many here forget that Chrysler has been using a cylinder deactivation system on the 5.7's since 2004 IIRC.
Clevy? Others?
Very few problems, works well and ask any owner. It is completely transparent in its operation and it always shuts down the exact same 4 pots...
Other than a funny sounding exhaust, apparently, theirs works pretty well.
Which is pretty amazing for Chrysler electronics...
Originally Posted By: MolaKule
I have a 5.3L V8 TrailBlazer and the same 4 cylinders are shut down for economic cruise and low power.
I would prefer a "rotating shudown" sequence of cylinder deactivation but my engine rebuilder says it has more to do with engine balancing, and the EC software would have to be more complex.
Interesting discussing.
there would also be more hardware required (only 4 cylinders have the special lifters and hydraulics that keep both valves closed during deactivation with the current systems), and testing showed its just not worth the trouble, at least on the Chrysler and GM v8s.
The only rotating-shutdown system I recall was the (shudder) Cadillac V-8-6-4 from the 80s. Good idea, but the technology was SO not there. That system used big solenoids to pull the fulcrum pins out of the rocker arms, rather than using a little low-current electrically operated valve to divert oil and collapse selected lifters.
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V8's (at least the American-style 90-degree crank variety) have the feature that the 4 cylinders that shut down are two per bank, not one whole bank like a v6. That might help keep everything more uniformly heated in a v8. As SteveSRT8 said, the Chrysler system has been bulletproof *except* for a possible timing chain failure mode unique to whatever programming is used in Challenger 5.7s. At least that's the buzz on the Challenger forums, and there does seem to be at least some correlation. Its never reported on a manual transmission Challenger, which never turns on cylinder deactivation. It also doesn't seem to happen on the Ram, 300, and Charger, but who knows about internet-reported phenomena like this.
I have a 5.3L V8 TrailBlazer and the same 4 cylinders are shut down for economic cruise and low power.
I would prefer a "rotating shudown" sequence of cylinder deactivation but my engine rebuilder says it has more to do with engine balancing, and the EC software would have to be more complex.
Interesting discussing.
there would also be more hardware required (only 4 cylinders have the special lifters and hydraulics that keep both valves closed during deactivation with the current systems), and testing showed its just not worth the trouble, at least on the Chrysler and GM v8s.
The only rotating-shutdown system I recall was the (shudder) Cadillac V-8-6-4 from the 80s. Good idea, but the technology was SO not there. That system used big solenoids to pull the fulcrum pins out of the rocker arms, rather than using a little low-current electrically operated valve to divert oil and collapse selected lifters.
edit>
V8's (at least the American-style 90-degree crank variety) have the feature that the 4 cylinders that shut down are two per bank, not one whole bank like a v6. That might help keep everything more uniformly heated in a v8. As SteveSRT8 said, the Chrysler system has been bulletproof *except* for a possible timing chain failure mode unique to whatever programming is used in Challenger 5.7s. At least that's the buzz on the Challenger forums, and there does seem to be at least some correlation. Its never reported on a manual transmission Challenger, which never turns on cylinder deactivation. It also doesn't seem to happen on the Ram, 300, and Charger, but who knows about internet-reported phenomena like this.
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If I remember correctly, the Honda Odyssey V6 had two different deactivation modes. It had 3-cylinder mode which deactivated an entire bank, and a 4-cylinder mode that deactivated one cylinder on each bank. In 3-cylinder mode, the engine firing order goes bang-skip-bang-skip-bang-skip. In 4-cylinder mode, the engine firing goes bang-bang-skip-bang-bang-skip. Honda had active motor mounts to counteract the unevenly spaced torque reactions in 4-cylinder mode.
The new GM 4.3 V6 also has a V4 mode, and is fitted with deactivating lifters on one cylinder of each bank.
The new GM 4.3 V6 also has a V4 mode, and is fitted with deactivating lifters on one cylinder of each bank.
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My Pilot also has the infamous VCM system. Despite what Honda wants you to believe, VCM is hard on the engine (particularly spark plugs + motor mounts) and oil. Because of this, I stick to a 6 month/5000 mile OCI using a good synthetic oil + filter combo.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
Originally Posted By: mclasser
My Pilot also has the infamous VCM system. Despite what Honda wants you to believe, VCM is hard on the engine (particularly spark plugs + motor mounts) and oil. Because of this, I stick to a 6 month/5000 mile OCI using a good synthetic oil + filter combo.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
thats what i do. ^^^
My Pilot also has the infamous VCM system. Despite what Honda wants you to believe, VCM is hard on the engine (particularly spark plugs + motor mounts) and oil. Because of this, I stick to a 6 month/5000 mile OCI using a good synthetic oil + filter combo.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
thats what i do. ^^^
Originally Posted By: mclasser
My Pilot also has the infamous VCM system. Despite what Honda wants you to believe, VCM is hard on the engine (particularly spark plugs + motor mounts) and oil. Because of this, I stick to a 6 month/5000 mile OCI using a good synthetic oil + filter combo.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
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Ditto. Make sure to only use Honda ATF DW-1 as other ATF fluids might cause issues.
My Pilot also has the infamous VCM system. Despite what Honda wants you to believe, VCM is hard on the engine (particularly spark plugs + motor mounts) and oil. Because of this, I stick to a 6 month/5000 mile OCI using a good synthetic oil + filter combo.
Also, due to Honda's shaky auto transmission history and this behemoth only having an archaic 5 spd auto, I'll be doing an ATF D&F every 1 yr/15K miles. Cheap insurance if you ask me.
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Ditto. Make sure to only use Honda ATF DW-1 as other ATF fluids might cause issues.
I have a 2013 5.3L with that AFM cylinder shut down thing. As opposed to wondering how it works and what oil would be best for it when it is doing it's thing, I just deactivated the AFM and all 8 cylinders work all the time.
I have a simple philosophy regarding this. I paid for 8 cylinders and they all must work all the time. I realize that the government has had a heavy influence in GM's thinking in the last few years, but I am not about to have the cylinders act like government workers and have 4 of them standing around watching the other 4 work. They day after I brought it home new from the dealership, I tore up the union contract that my cylinders had negotiated and established a team environment where every cylinder has to pack the gear. AFM fully non-functional. No goofing off allowed. Many other owners have done their own anecdotal testing on the mpg difference between non-AFM and AFM, and it is a wash. Some claim better mpg with it off, with it on, and some see no difference. Since I live rural and the vehicle is used for around the farm and not as a daily driver to work, the difference in mpg, if there is any, is a non-issue.
Now, given the TSB's that GM has put out about problems with these engines down the road, especially as it relates to oil consumption issues, I didn't want to chance anything. It is bad enough that GM now says that using a quart every 1000 miles is appropriate and they won't even discuss oil consumption till it exceeds that by a fair amount.
I have a simple philosophy regarding this. I paid for 8 cylinders and they all must work all the time. I realize that the government has had a heavy influence in GM's thinking in the last few years, but I am not about to have the cylinders act like government workers and have 4 of them standing around watching the other 4 work. They day after I brought it home new from the dealership, I tore up the union contract that my cylinders had negotiated and established a team environment where every cylinder has to pack the gear. AFM fully non-functional. No goofing off allowed. Many other owners have done their own anecdotal testing on the mpg difference between non-AFM and AFM, and it is a wash. Some claim better mpg with it off, with it on, and some see no difference. Since I live rural and the vehicle is used for around the farm and not as a daily driver to work, the difference in mpg, if there is any, is a non-issue.
Now, given the TSB's that GM has put out about problems with these engines down the road, especially as it relates to oil consumption issues, I didn't want to chance anything. It is bad enough that GM now says that using a quart every 1000 miles is appropriate and they won't even discuss oil consumption till it exceeds that by a fair amount.
TiredTrucker : how did you deactivate the AFM ? pulling a fuse or a reprogram; kinda interested in this as I would consider a GM if, and only if, I could de-activate this nonsense.
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