I know this has been asked before, but I couldn't find the post. I received this e-mail from someone on an Olds mailing list. What would you guys suggest? Or can anyone post the link to the thread where this has been discussed?

Hello again Folks, a good friend of mine found about 30 qts. of oil in his fathers garage. all have never been opened but some of them may be 10-15 years old.. With the price of oil around $3 a qt. he would really like to use it but do you think it's still good after all this time

Thanks!