San Francisco Zephyr By Angela Cotey | February 20, 2020 | Last updated on August 8, 2025 Email Newsletter Get the newest photos, videos, stories, and more from Trains.com brands. Sign-up for email today! Get Updates New EMD F40PH diesels lead the westbound San Francisco Zephyr east of Denver in June 1981. Amtrak acquired more than 200 such locomotives in multiple batches. Bob Johnston photo