While on the road, I talk up Shields Rv Park and many of the people with whom I speak want to know if diesel is available on base and the answer is "yes." The Naval Exchange has store near the east entrance where gas and diesel are available at prices at or below most off base facilities. I travel between Corpus Christi and San Antonio frequently and I have found that the cheapest diesel is found at Exit 9 on IH37 and further up the road at the George West exit.
Also there have been questions about the availability of propane within the park and again the answer is yes. A local distributor makes a weekly visit to the park to top off those who ask for it.