Seeing that the majority of new gas trucks arriving on lots have the 3.73 gear ratio, I thought I'd share a way to find trucks with the 4.30 axle. This may be helpful if you're trying to find one to test drive. There's probably other methods, but this worked for me. Allows searching across the whole US.

1. Go to cars.com.

2. Do a search for new F250 and/or F350.

3. When search results appear, go to "More Options" and under "Additional Keywords", put "4-30" without quotes. The filter doesn't like numbers so it will reject 4.30, but it will work with the dash.

4. Add other search filters as desired.