Oil Strategy To Prevent Carbon Piston / Ring Deposits ?

As amy those have seen a few of my posts you know I voluntarily announced my OSIs at 2500. Up until the next change I was using Amsoil Signature Series oil. The next change I am switching to HPL EURO 5W40 and staying with the 2500 OCI. I also use Amsoil’s Oil Bypass system; 2 filters, the Bypass 2 micron filter and the 20 micron Full Flow filter. I have been running the Bypass system for the life if my truck - 66K right now.

I have seen reports of GM trucks burning oil since the day I bought my truck. I check my truck oil daily. I have never burned/leaked a drop…none. I also use Amsoil’s upperend cleaner/lubricator once every OSI.

No burned or leaked oil. None.
 
Our ‘26 Carnival calls for 0W-20 and 5,000 mi “severe duty” OCI’s.

I run and will continue to run for the foreseeable future Mobil 1 ESP 0W-30 with 4-5,000 mi OCI’s.

Fuel system cleaner gets used once per OCI.
 
How do you think that prevents piston deposits?
I dont think. I know.
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Note: does not work on European cars. You could have a 30 mile oci and they'll still carbon up. Idkw.
 
I dont think. I know.
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Note: does not work on European cars. You could have a 30 mile oci and they'll still carbon up. Idkw.
I'm asking you to explain the mechanism. I've torn down 302's with extended OCI's (on M1) and the pistons looked fantastic. You've seen AMSOIL's recent pictures of Sequence IIIH.

Also, as CCN has shown in his Toyota teardowns, COO doesn't dictate whether an engine develops piston deposits or not.
 
Why not play it safe and do the VRP 4 OC full cycle and afterwards make your own subjective decision, noting any changes in idle, power, etc.? You have nothing to lose.
 
I'm asking you to explain the mechanism. I've torn down 302's with extended OCI's (on M1) and the pistons looked fantastic. You've seen AMSOIL's recent pictures of Sequence IIIH.

Also, as CCN has shown in his Toyota teardowns, COO doesn't dictate whether an engine develops piston deposits or not.
Form what ive seen the main mechanism is neglect.
You say it's the engines patman says it the oil. Which is it?
I asked which oils and never got an answer, I and I'm sure many others would probably like to know what oils to avoid.
 
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I don't believe that anybody actually knows because everything here is basically anecdotal with respect to determining if you have carbon or not, where that carbon is coming from, etc.
Yes and if your engine doesn't burn any oil, there is less carbon to build up.
 
As amy those have seen a few of my posts you know I voluntarily announced my OSIs at 2500. Up until the next change I was using Amsoil Signature Series oil. The next change I am switching to HPL EURO 5W40 and staying with the 2500 OCI. I also use Amsoil’s Oil Bypass system; 2 filters, the Bypass 2 micron filter and the 20 micron Full Flow filter. I have been running the Bypass system for the life if my truck - 66K right now.

I have seen reports of GM trucks burning oil since the day I bought my truck. I check my truck oil daily. I have never burned/leaked a drop…none. I also use Amsoil’s upperend cleaner/lubricator once every OSI.

No burned or leaked oil. None.
Those "20 micron full flow oil filters" are actually pretty good at stopping particles down to the 1 and 2 micron range.
Those bypass filters really don't do anything especially when you change your oil somewhat on time.
I say if an engine is known to burn oil or needs 2,500mile oci to not burn oil that is a great reason to not buy a vehicle with that engine.
 
Form what ive seen the main mechanism is neglect.
You say it's the engines patman says it the oil. Which is it?
I asked which oils and never got an answer, I and I'm sure many others would probably like to know what oils to avoid.
It can certainly happen from neglect, but I wouldn't classify that as the main mechanism.

You are familiar with Sequence IIIH, and its predecessor IIIG, correct?
 
Step 1. Don’t buy trash direct injection gasoline engines.
I agree at a high level, but when shopping to replace the 2022 Audi Q5, my wife wanted the third row seating and I wanted a naturally aspirated engine. Unfortunately, the Toyotas have either gone hybrid or turbo. I do like that their engines use port and direct injection, but not willing to get a turbo to have it. Thus, the 2025 Pilot. Now I have to live with that decision.

Based on what the Gold Eagle guy has shared with us, the VRP FSC does provide some intake valve cleaning by way of the PCV system. No doubt at a minuscule level compared to port injection. This is also why I'm running Shell premium.
 
As amy those have seen a few of my posts you know I voluntarily announced my OSIs at 2500. Up until the next change I was using Amsoil Signature Series oil. The next change I am switching to HPL EURO 5W40 and staying with the 2500 OCI. I also use Amsoil’s Oil Bypass system; 2 filters, the Bypass 2 micron filter and the 20 micron Full Flow filter. I have been running the Bypass system for the life if my truck - 66K right now.

I have seen reports of GM trucks burning oil since the day I bought my truck. I check my truck oil daily. I have never burned/leaked a drop…none. I also use Amsoil’s upperend cleaner/lubricator once every OSI.

No burned or leaked oil. None.
I have owned six 5.3L GM’s … None have burned oil …
 
What I've found which seems to work the best for my 2025 Honda Pilot is using Shell V-Power Nitro+ at every possible fill-up. I've also switched to HPL Premium Plus PCMO, but was previously using Amsoil Signature Series, so believe the biggest difference is using the Shell premium.

My Pilot now is approaching 22k miles. When I bought it, I used Shell premium, then switched to using a less-expensive, 87-octane, Top Tier gas. I soon noticed seeing quite a bit of carbon when cutting open the oil filters. After switching back to Shell premium, the last oil filter had minimal carbon deposits.

When Valvoline Restore and Protect Fuel System Cleaner was released, I used it about half way through the first OCI of HPL (switched at 13k miles) and now into my second OCI of HPL, added another bottle of VRP FSC about 1k miles ago. BOGO sale on VRP FSC ends July 27th.

Honda's J35Y8 engine is known for its prolific carbon-depositing. One contributing factor is its Variable Cylinder Management system, which turns off the rear bank of 3 cylinders. On this iteration of the J35 engine, running in Sport or Two drive modes prevents VCM from engaging. I now only run in one of those two modes.
How do you know what prevents piston ring deposits after all of 22k miles? Have you inspected the rings?
 
I have said, if starting over on my Pilot, I'd be using Valvoline Restore and Protect at ~5k OCIs. I have several years of HPL, so not making any more changes to my oil strategy.

I bought a 24 Sport hybrid for the Mrs
It had 33k
I plan to use VRP with a Microgard Select.
I am planning a 3k oil change and will have the fuel dilution checked.

if the dilution numbers are ok, I’ll move to a 5k OCI
 
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