The article on the following link contains some useful information about OAT, HOAT and IAT coolants, their use in pre-2005 vehicles and an example of the problems that may arise from using the wrong coolant.

http://rrtechnical.info/miscellaneou...oatwarning.pdf

The following link to a Valvoline product suitability guide for the major vehicle manufacturers might also be useful:

http://www.valvoline.com/pdf/Zerex_CoolantChart.pdf