comparison between john deere 6068tfm and cumming 4b-250

Hi, gjct-ag!

I was unable to find any head-to-head comparisons of these two
powerplants online, but I have located spec sheets for both.  This
will at least allow you to look at them seriously and draw your own
conclusions.

Here are specs for the John Deere from their website:
http://makeashorterlink.com/?A56F23421

Here are the specs for the Cummins engine, from their website:
http://makeashorterlink.com/?H5AF23421

Of the two, the Deere offers less power but also lower fuel
consumption.  The Cummins, on the other hand, is more powerful and
lighter in weight.  Both, of course, are highly reputable companies
and the availability of parts and service should be similar in most
areas.

Each engine has its strong points.  You'll want to make your purchase
decision based on which features are more important in your
application.

Thank you for your inquiry.

Hello again.

After going to bed last night, it occurred to me that I hadn't
documented my search strategy for you.  I used various combinations of
the following keywords:

"John Deere" "Cummins" "marine diesel" review comparison comparative
table report

Although I did not find anything on-line using these keywords, it is
quite possible that one or another trade magazine has published some
sort of comparative review, and that it is just not available on-line.
 You may wish to pursue this avenue by contacting a few of the major
publications.

Thanks again!