No problem if the viscosity change (it'll increase when cold) isn't a
problem for you.

For what it is worth, ALL aviation oils are compatible, regardless of brand.

KB

"Roy Page" wrote in message
k.net...
I am running my Archer on Aeroshell 15W50.
The Lycoming 0-360 burns about a quart of oil every 12 hours.
I have a case of Aeroshell W100 and have no use for it and everybody at
our field uses a multigrade.
I was watching an Aeroshell video and was surprised that it implied that
all Aeroshell oils were compatible.

What is the Forums opinion on topping up 15W50 with W100.

Roy