Since I started this thread - some follow-up. The Petroleum Quality Institute rates motor oils, and this link shows that Chevron Delo 400 has quite a bit of zinc and phosphorus. Might be a good oil to run in an FJ40, at least for the summer (15w-40).
There's a ton of good info at the main level of this site - they test ATF and car-rated motor oils.
Steve H. - KE0KNH
Colo Springs, CO
'78 FJ40, '89 FJ62, '98 4Runner