Hi everyone,

Apologies in advance if this is a really dumb question

When I purchased my V8 Vantage, the original owner gave me a few quarts of Castrol fully synthetic 5w-50 motor oil which he had picked up from his local AM dealer (that was the oil his AM dealer had been using).

However, my local AM dealer uses the Castrol 10w-60 oil that is recommended per the owner's manual.

Now, before every day (keeping in mind I only drive my car about once or twice a month), I check the oil level and in the course of the 9 months that I've owned my car, I've had to add in total about 1/2 quart of oil.

So far, I've been adding the same Castrol 10w-60 oil but I wondering if I could also make use of the 5w-50 that the original owner left behind....keeping in mind that this would only be used on those few occasions when I need to add a bit of oil.

Long story short, can I mix a small amount of 5w-50 oil with the 10w-60 that is in my car? Both oils are Castrol branded and both are fully synthetic.

If it's not a good idea, anyone in the area that wants some free 5w-50 oil?

 

Answer is yes, go ahead and mix it in.

 

No worries, you can, it's not worth buying oil just for top-ups..mix away!!

 

mixing is OK in my opinion and I've certainly done it (we are talking about 0.1:1 ratios here for a top-up case and not a 1:1). The most important thing is not to drive with LOW oil level.