My understanding of CamGuard having talked to many mechanics and engine shops of varying backgrounds over time is the plane should fly regularly and if so shouldn't have any issues with wear. I know, I know -- regularly is a vague term and not every can afford to simply fly their plane all the time. If it's only flying once per month (or less) then you definitely need the additive to help keep a protective film on the cam which prevents corrosion and eventual wear.

We run the Phillips 20W50 X/C exclusively in our entire fleet. Engine mix includes O-320-D2Js, IO-320-B1As in our PA-30, IO-360-CIC, IO-360-M1A, IO-360-L2A, and even the IO-240-B3 when I had the DA-20. I don't use CamGuard in any of these engines because they fly multiple times per week, with the 172s flying several sorties per day. We change oil and filters every 50 hours, take oil samples every 100 hrs, and knock on wood have not yet had a lubrication related problem with any of them. One of our O-320s is currently at 2300 SMOH and running perfectly fine.

In consultation with several engine shops (trust but verify) we are even using the Phillips now as the break in oil when we do our engine changes. We've done this twice now with our last two O-320 swaps and break in occurred without any drama and oil consumption stabilized within 12-15 hours each time.

Tim

Edit: I forgot to add, we are located in the mid-Atlantic (just outside of DC) and we run this oil year round.

I have Savvy Aircraft help manage my maintenance and they strongly recommend CamGuard as well as Blackstone oil analysis.

If you're concerned enough about your oil to be changing it so frequently, I think you should seriously consider sending samples to Blackstone for analysis.

I understand those who rebuild at TBO. My attitude is that oil sample testing and filter magnetic strips (along with external observable changes in temp and performance) will tell me when it's time to tear the engine down. I've experienced impending engine failure after a rebuild or new engine change as often as I have from a high mileage version.

No that I'm home based in New England I have switched to 15w50 cause it's cold out there!

I also religiously use Avblend. It's an anti wear additive we used in the Navy in all aircraft engines. It is used in oil and gas so impacts the entire engine. It's basically the aviation version of Zmax for cars. Use it there too. Kept me out of the drink in the fleet so why change a good thing. Believe it or not..Avblend is cheaper than Zmax but is an identical formula according to the manufacturer. Go figure.

At any rate, while this is my practice and experience offered for what it's worth, and is not an attempt to advocate to others.