Hello mperk,
I too was worried about my first oil change in my '52 2-ton with a 235 (no filter). A friend told me I need to use only detergent oil (expensive and difficult to find). Someone else suggested I use only 50wt non-detergent. I looked around this site and saw several other suggestions. I finally decided to go with Super Tech 10W-30 (Wal-Mart brand) for our upcoming Wisconsin winter and then 10W-40 for summer. It took just less than 5 quarts. I hope this helps. Good luck.
