Most of the john deere turbos that I have seen run a fairly large exhaust housing and have lots of blades on the comp wheel which makes for low air flow volumes and typically does not work very well as a performance turbo on a 5.9l cummins.
John deere generally uses Schwitzer turbos from what I've seen. However, I bet that there are a lot of different turbos that they use. Also, many of them have the t3 flange and will bolt directly onto the stock dodge manifold, however, that doesn't mean its an upgrade. Since many ag and equipment diesels turn low RPM and have a low power out put, a lot of airflow isn't needed so the turbo may not be that big. Find out the true specs of it and go from there.
Find out, compressor inducer size, Exhaust turbine exducer size, and exhaust housing A/R or size in cm^2. Also is it wastegated, non wastegated etc...
A forum community dedicated to Diesel engine owners and enthusiasts. Come join the discussion about performance, builds, ecodiesel, towing capacity, modifications, classifieds, troubleshooting, maintenance, and more!