Mixing leftover oil?

[Valk1500]

I have a 5 qt. and 4 qt. container of leftover oil in my garage from 8 months ago, each has 2 quarts left. Is it safe to mix:
2 quarts of M1 15w-50
2 quarts of Shell Rotella 15w-40
3 quarts of (fresh) Havoline 5w-30
to come up with what I estimate to be:
10.7w-38.6

I would be using it in an F-150, 5.4L Triton with 67,000 miles on it?

 

[userfriendly]

You need an ASTM blending chart and all of the typicals to come up with the exact SAE grade, but it looks like a 10W40 to me.
Don't you have an old beater to use up those odds and ends on instead of your good truck?

 

[Jason8691]

I agree with UF, dont put that in your truck! Experiment with your lawnmower first

[ October 26, 2003, 08:42 PM: Message edited by: Jason8691 ]

 

[labman]

Maybe one more reason to contine my mindless sticking to the same old thing.

 

[Pablo]

Maybe a logical mixing of two oils can be OK if you do the research, but just throwing together leftovers....we'll I'll support you and say: mix those three and go 3000 miles max. Probably won't completely destroy your engine.

 

[sHERM]

Why take the chance, spend the 7.00 for new oil

 

[greencrew]

That's some thick oil for a 5.4 Triton in November.

 

[mf150]

The most I go with in a Triton engine is 10W30. Anything heavier and the OHC may experience some start up starvation or at least some gas milage drop.

Also, most oil companies do not suggest mixing oils. Each comes with it's own chemical package. To ix chemicals may nullify others out causing teh oil to be less effective.

 

[javacontour]

Why not just buy enough of the 5W30 to do a complete change?

You could use one of the others as a make-up oil if that is needed.

Then in the spring, you could do the same with one of the 15W40 flavors

TB