I have several legal questions?

My boyfriend and I were together 7 years in the state of PA. We were engaged and to be married this year. He died suddenly and unexpectedly on Jan 19 of this year. He had finaced a truck in his name and with a friend/boss. He paid the truck in full of 2010 and his friend was supposed to be taken off the title as lien holder. He has not and is now claiming the truck as his. Is there anything I can do to pursue this? I need his title so that I can go on with things. The bill, insurance and registration were all in his name. I also several death certificates in my possession. What can I do?