Power Service made the diesel oil extender to replenish additives between high mileage oil changes. Some stores still have some but PS recently stopped making it. Contacted PS and they said it contained 10,000ppm zinc - that's almost 10times what the older oils had. If you combined 1 quart oil extender to 10 quarts of oil, it would boost the zinc level to 1000ppm per qt. WalMart still had some of this oil extender; have seen it in truck stops too. Even though short term, hope this helps.
bttt http://www.powerservice.com/diesellube_oilextender.asp The website doesn't make mention of ZDDP specifically & a google search turned up info on this from about '05 or so. Reading between the lines, looks like they may have been lead-turning the reduction in ZDDP for cars (late '05 early '06) & trucks ('07). The google search turned up very high praise for PS diesel fuel additives across the board, but not a lot for the oil extender - probably because CI is still available...
A rep from the company emailed me back when I inquired about ZDDP - he affirmed that 'PS Diesel Oil Extender' was around 10,000ppm. Went to a swap meet in LongBeach Ca 6/10/07 and there was a Lucas Oil booth. They also were aware of the concern of reduced ZDDP and cams going flat. They have products that also cure the ZDDP reduction problems of newer blended oils.
The Jalopy Journal
