AS W100 vs X/C 20W-50

[PT20J]

I have about 170 hours on the factory rebuilt IO-360-A3B6 in my 1994 M20J. The first 40 hours I ran it on straight Aeroshell 100 for break in. Then I ran it on Aeroshell W100 for another 100 hours during which time it pretty consistently burned 1 qt every 8 hours. I tried my long-time practice of running it down to 6 and filling to 7. I also tried running it down to 5 and filling it to 6. Didn't matter. Eight hours/qt. At 140 hours, I switched to Phillips X/C 20W-50. Now it consistently gets 12 hours/qt. Cheaper oil and less of it seems good to me. I have no idea why the difference, but the C-210 owner in the hangar next to me had the same experience. Curious if anyone else had similar (or opposite) results. (A C-175 owner in the hanger nearby got less oil consumption switching from X/C 20W-50 to AS W100).

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[takair]

1 minute ago, PT20J said:

I have about 170 hours on the factory rebuilt IO-360-A3B6 in my 1994 M20J. The first 40 hours I ran it on straight Aeroshell 100 for break in. Then I ran it on Aeroshell W100 for another 100 hours during which time it pretty consistently burned 1 qt every 8 hours. I tried my long-time practice of running it down to 6 and filling to 7. I also tried running it down to 5 and filling it to 6. Didn't matter. Eight hours/qt. At 140 hours, I switched to Phillips X/C 20W-50. Now it consistently gets 12 hours/qt. Cheaper oil and less of it seems good to me. I have no idea why the difference, but the C-210 owner in the hangar next to me had the same experience. Curious if anyone else had similar (or opposite) results. (A C-175 owner in the hanger nearby got less oil consumption switching from X/C 20W-50 to AS W100).

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Are you using additives?  Did you consider Phillips 66 Victory?  I am near completion of my break in, so looking for my next oil.  Your results seem positive.

[markgrue]

The company I work for has 29 aircraft and we use Aeroshell 15w50 in everything.  Before we ran phillips xc in the twins with the Lycoming additive.  They also ran 80 in winter ane 100 in summer.  Now with just one oil in everything all the time it simplifies the whole thing and we don't have to buy the $45 bottles of additive.  I have always run Aeroshell 15w50 in my C and never regretted it.  I don't really keep track of how much it uses but I doubt it is more then a couple qts between oil changes.  I change oil at 25 hours though because I don't have an oil filter  Just a screen.

 

Mark

[PT20J]

I'm less concerned about additives since I got the roller lifters and fly it regularly. The X/C is cheap and seems to work, so I'm going to stick with it.

[philiplane]

You might try the 20w50 Victory instead of the plain XC, it has the Lycoming anti scuff additive, which is beneficial to a lot of parts beside the camshaft. Or use Camguard with the XC.

Anti-corrosion oils or additives are needed for planes flying less than 300 hours per year, which is most of the fleet outside of the training environment. 

I've used all the major brands of oil, in low time owner flown planes, and in high utilization fleets. Phillips is the best value, and as you've found, it can correct excess oil consumption problems that Aero Shell is known for. The 20W50XC is good for most applications, and their 100AW is good for planes that don't see temperatures below 40 degrees. 

Shell recently cut the size of a "case" to six quarts, to make their oil seem less overpriced than it is. They're getting a lot of laughs from commercial operators, who have been switching to Phillips over the past few years.

[MB65E]

Not really sure if the cold flow test prove anything but I’ve seen them done with Xc and as100+. The AS100 looks like it would lube things better to me. I’ve always run Aeroshell 100 in every engine except one guys T182T, he uses the XC and flys about 200hrs/year. 
I’d be interested as well with additional findings. 
I run AS100+ in my io360 on the Mooney. It’s oil is always really dark when drained. I’ve never seen anything except a foamy coffee color come out of the 182 with the XC. (EST 20hrs between changes. AS15/50 was always foamy coffee color too no matter how hot you ran the oil. 
-Matt 

[bradp]

I’ve also noticed that @PT20J... my consumption varies with season. I used to run XC +CG in the winter and W100 in the summer and would find my consumption would always go up slightly with the aeroshell. 

[gsxrpilot]

I used to do the same as @bradp in that I ran Aeroshell in the summer and Phillips in the winter. But I've been running the Phillips XC since I bought some cheap cases at Oshkosh and plan to just stick with it. I just ordered a couple of cases of the XC from  https://aviationoiloutlet.com/  on the recommendation of @PilotFun101.