i used 5w30 for the first 200 miles or so on my new engine. it was a constant reminder to change it out -- it really made my valves tick badly.

i run 10w40 year round, works the best in my experience.

'79 sport 4x4 longbed <img src="/forums/images/graemlins/smile.gif" alt="" />
20/22R hybrid with EB's OS valves, 268c cam, offy intake, weber 32/36, thorley header, 5 speed swap, 34" LTBs, downey 3" springs, marlin hysteer, 4.88s and locked

'91 4x4 shortbed
22R-E, W56, the dd!