I don't know what it is exactly, but Engravers Gothic, except for the J, is practically a match.

If you only want the logo you could look here

I had a quick look at the file in Illustrator, and it appears to be very cleanly drawn, it certainly isn't an auto traced job.

agreeing with Chesh.
fwiw, Doyald Young was responsible for the previous mark
and he discussed it on p. 156 of his book, Fonts and Logos.
(it was modified Franklin Gothic wide).

Here is a small article about Landor's makeover.

http://www.corporatelogo.com/articles/171feat1.html

The John Deere logo was probably based on Trade Gothic Extended.
All the characters match, but of course you can tell it's adapted because
of the heavier weight and small caps.