Hi Mike,

I've got an I-4 gasser, née diesel,  that also runs a little warm on
the oil.  I installed the larger oil/coolant heat exchanger, but it
didn't make a noticeable difference.  I'm about to do a big cooling
system overhaul/update to address some leaks, and recently ran across
some interesting info.  In case you haven't already done it, check out
the "Aux Oil-Cooler Modification" here:

http://www.vanagondiesel.info/index.php/Conversion_Related#Cooling_System

Apparently in the normal config, the oil heat exchanger only gets flow
when the thermostat is open.  I've noticed this in my van...the oil
only really starts warming up after the coolant has already come to
temperature.  The mod gives the heat exchanger flow all the time and
more of it.  I plan to do this and hope it will both speed oil warm-up
and lower max temps.

Alex