Honda V6 rear bank stuck rings and using oil

[Bill7]

Our odyssey oil change computer comes up around 5k, so that does seem to be the right interval.

I have had the van muzzled most of its life. Currently it isn’t, but I will again at some point (figure it’s good for the system to operate to some extent).

The engine is prone to some varnish, which is something I’m not used to. It has seen synthetic oils 0w-20 its whole life. Runs great and smooth. MPGs on on the highway (we can get 30 if super careful and zero traffic, usually 28), but poor around town.

Good post JHZR2. Knowing what you know now about the varnish, if you could do it over from day 1, what oil change interval would you have chosen to prevent any varnish?

 

[JHZR2]

Good post JHZR2. Knowing what you know now about the varnish, if you could do it over from day 1, what oil change interval would you have chosen to prevent any varnish?

Probably nothing different tbh. It has 100k and minor varnish. I’ve never pulled a VC to assess in earnest.

I’d probably just run HPL cleaner more.

 

[Bill7]

Probably nothing different tbh. It has 100k and minor varnish. I’ve never pulled a VC to assess in earnest.

I’d probably just run HPL cleaner more.

I have 4 Honda Odyssey's years 2006 to 2007 all with VCM enabled.
I'm doing 4k miles / 6 month (whichever comes first) oil change intervals with a low priced full synthetic 5W-30 (not 5W-20) which has the GM Dexos 1 Gen 3 approval which has stricter limits for sludge/varnish deposits.

I'm using a solvent engine flush with every oil change.
I am also doing 1 quart HPL EC 30 + 3.5 quarts full synthetic with each oil change interval.
After a discussion with Dave from HPL, 2 oil change intervals during the next 12 months with 1 quart HPL EC 30 might with each oil change might be enough to make good cleaning progress on any varnish.

I know it sounds a bit extreme, but I would rather use a bazooka than a BB gun at this.

 

[RooflessVW]

I have 4 Honda Odyssey's years 2006 to 2007 all with VCM enabled.
I'm doing 4k miles / 6 month (whichever comes first) oil change intervals with a low priced full synthetic 5W-30 (not 5W-20) which has the GM Dexos 1 Gen 3 approval which has stricter limits for sludge/varnish deposits.

I'm using a solvent engine flush with every oil change.
I am also doing 1 quart HPL EC 30 + 3.5 quarts full synthetic with each oil change interval.
After a discussion with Dave from HPL, 2 oil change intervals during the next 12 months with 1 quart HPL EC 30 might with each oil change might be enough to make good cleaning progress on any varnish.

I know it sounds a bit extreme, but I would rather use a bazooka than a BB gun at this.

I don’t get why you’d do all that work just to leave VCM enabled…

 

[Bill7]

I don’t get why you’d do all that work just to leave VCM enabled…

VCM enabled means less money spent on gasoline as I drive with a light foot and vehicle runs only on 3 cylinders most of the time.

 

[RooflessVW]

VCM enabled means less money spent on gasoline as I drive with a light foot and vehicle runs only on 3 cylinders most of the time.

Money saved, eh?

That you then spend on too frequent oil changes, HPL, flushes...

 

[Bill7]

Money saved, eh?

That you then spend on too frequent oil changes, HPL, flushes...

Gasoline is approaching $4 a gallon. Oil changes happen every 6 months.
Gasoline savings are more important to me.

 

[RooflessVW]

Gasoline is approaching $4 a gallon. Oil changes happen every 6 months.
Gasoline savings are more important to me.

Have you tried disabling VCM?

On my 22 it's about a 1 mpg difference, if even that.

 

[Bill7]

Have you tried disabling VCM?

On my 22 it's about a 1 mpg difference, if even that.

VCM enabled hasn't caused any issues yet for me.

Just wanting to clean up any sludge or varnish that might be already there so I can go another 100k miles in each of my 4 Honda Odysseys.

 

[nicholas]

My weekly trip to Bill's shop yielded another interesting discussion with one of the mechanics.

He was working on replacing rear pistons/rings of all three of the rear cylinders on a Honda Odyssey van with about 125,000 miles on the clock. He said he does about one/month and it's always the rear cylinders that have stuck rings and use so much oil that the plugs get fouled. The front cylinders are always fine and have normal compression. This mechanic has about 40 years of experience and is serious about making a living working on cars. He can turn the rear bank piston replacement job in about 7 hours. It's fun to watch him work.

As far as he knows, they all run bulk oil and some owners neglect oil changes. Would a better oil help?

Why only the rear cylinders?

No oil will help.
At the ody forum, where I have been for 2 years. Every week 1 or 2 new people come in with this issue.

Its the VCM honda uses to save 1 mpg. At the expense of customer engine reliability.

Putting a vcm blocker or muzzle is the only way to stop this issue from happening.

It's nasty. Honda has known about this and was taken to court during the group 2 series of this 3.5 engine.
They still use vcm today on the 3.5.......Jenks.

 

[nicholas]

The issue is most prevalent on the VCM motors from 2005-10, but on the Odysseys, up until 13-14. The newer ones do not seem to be affected, despite having VCM.

I'm in the gen 3 forum....every week 1-2 people pop in with this issue.
As the gen3's get higher in mileage this issue pops up.
Lots of highway=lots of shut off cylinders and gummed up rings.
It's a nasty engine design.

 

[Shel_B]

Hmmm. I see all the varnish and gunk on the front bank in these engines. I supposed that. Valve train condition foes not translate to the condition of the cylinders.

Another vote for 0w-40 or HM Mobil as those are proven to clean as well with 5K or less oil changes to keep things clean.

Are you able to provide some specific info that says M1 HM has the ability to clean an engine? Since M1 makes HM oils in a couple of flavors, which HM are you referencing?

 

[nicholas]

Th

On the 3rd Generation Pilot Forum (2016-2022) there are reports of the VCM 3 affecting the 6 speed transmission torque convertor. The VCM 3 allows for "planned slippage" of the torque convertor at certain times to mask vibrations resulting from the cylinder deactivation. This is allowing the fluid to deteriorate quicker with wear material and eventually may cause transmission problems also.

Honda came out with a service bulletin to drain and fill the fluid 3 times and update the software if the new fluid didn't "fix" the problem. More and more reports of torque convertors needing replacement. What's somewhat odd in my opinion is that only the 6 speed transmissions which use Honda DW-1 fluid are having this problem.

The 9 speed transmissions which my 2019 Pilot Touring has uses Honda 3.1 fluid and there are no service bulletins for the same problem with that transmission. The Honda Maintenance Minder from owner reports calls for the 6 speed fluid to be changed about every 30000 miles but the 9 speed every 60000 miles.

The 9 speed uses a good German syn atf.
Oem honda is dino garbage.

The gen 3 ody has the exact same issue.
Even worse because it usually tows more people.

 

[willbur]

Have you tried disabling VCM?

On my 22 it's about a 1 mpg difference, if even that.

I think I recall an article that stated the VCM enambled an Odessy to get 18% better mpg over the equivalent Toyota van

 

[RooflessVW]

I think I recall an article that stated the VCM enambled an Odessy to get 18% better mpg over the equivalent Toyota van

I believe that.

 

[supton]

I thought VCM was also hard on motor mounts too? thought I read on here the other day that the TC was commanded to slip extra too, but that might be only the latest generation.

With VCM disabled, isn’t the non DI 3.5’s relatively easy on oil? Decent synthetic and 10k OCI?

 

[SubieRubyRoo]

Have you tried disabling VCM?

On my 22 it's about a 1 mpg difference, if even that.

On my 06 which is the same as Bill07 has, the muzzler “cost” less than 0.6 mpg. I went about 10k miles before I muzzled it and had hand-calculated averages. Then I muzzled it and drove it another 30k before giving it to my stepson.

You’re talking about roughly 12 miles difference per tank, or less than half a gallon, so $2 per fill-up. On 5k OCIs, about $16 saved in gas. My UOA on Pennz Euro 0w40 in that van showed the oil was still in great shape at 7500 miles.

 

[willbur]

I have 4 Honda Odyssey's years 2006 to 2007 all with VCM enabled.
I'm doing 4k miles / 6 month (whichever comes first) oil change intervals with a low priced full synthetic 5W-30 (not 5W-20) which has the GM Dexos 1 Gen 3 approval which has stricter limits for sludge/varnish deposits.

I'm using a solvent engine flush with every oil change.
I am also doing 1 quart HPL EC 30 + 3.5 quarts full synthetic with each oil change interval.
After a discussion with Dave from HPL, 2 oil change intervals during the next 12 months with 1 quart HPL EC 30 might with each oil change might be enough to make good cleaning progress on any varnish.

I know it sounds a bit extreme, but I would rather use a bazooka than a BB gun at this.

wwillson June 4 - My weekly trip to Bill's shop yielded another interesting discussion with one of the mechanics.
He was working on replacing rear pistons/rings of all three of the rear cylinders on a Honda Odyssey van with about 125,000 miles on the clock. He said he does about one/month and it's always the rear cylinders that have stuck rings and use so much oil that the plugs get fouled. The front cylinders are always fine and have normal compression. This mechanic has about 40 years of experience and is serious about making a living working on cars. He can turn the rear bank piston replacement job in about 7 hours. It's fun to watch him work."

You have me confused. You replied in one of your posts regarding VCM issues that the FRONT cylinders are the damaged ones and how really tough those cylinders are on the oil. Did I misunderstand you?

 

[Bill7]

"My weekly trip to Bill's shop yielded another interesting discussion with one of the mechanics.

He was working on replacing rear pistons/rings of all three of the rear cylinders on a Honda Odyssey van with about 125,000 miles on the clock. He said he does about one/month and it's always the rear cylinders that have stuck rings and use so much oil that the plugs get fouled. The front cylinders are always fine and have normal compression. This mechanic has about 40 years of experience and is serious about making a living working on cars. He can turn the rear bank piston replacement job in about 7 hours. It's fun to watch him work." WWilson June 4

Bill7- you have me confused. You

replied in one of your posts regarding VCM issues that the FRONT cylinders are the damaged ones and how really tough those cylinders are on the oil. Did I misunderstand you?

I have two 2006 Odysseys and two 2007 Odysseys which have VCM version 1.
Their front cylinder heads (in the direction of the front bumper) get extremely hot when VCM engages and the rear bank shuts down near the firewall. This cooks the oil on the front cylinder heads due to a poorly designed PCV system and creats a lot of varnish on the front cylinder heads.

My Odysseys have the regular tension piston rings so they don't burn oil.

This is a totally different issue than the newer Odysseys with VCM version 2 which have the low tension piston rings.

 

[Passport1]

My son has a 2016 Odyssey. Has had a diet of Valvoline synthetic 0W-20 since new. At about 83K miles it fouled out the plug on the back bank driver's side. Think that's #3. I changed the plug and added a muzzler. Van is still running fine now with ~100K. It did have the Honda transmission shudder two years ago. Honda shop changed the fluid and reflashed the computer. No issue since. It seems Honda in it's zeal to find more mpgs found only trouble.