WSS vs ESE Coolant

[Reg Bichel]

G'day Fellas,

My truck is an Aussie 2005 7.3Ltr Powerstroke.
It is essentially the US 2003 7.3Ltr. Australia wasn't a signatory to the Cal Emmission laws so continued to plant the 7.3Ltr donks into our RHD F-Trucks up until late 2005.
My truck wasn't registered until February 2006.
The International 7.3Ltr donk in mine was manufactured in 2004.

The manual which came with the truck states that the correct coolant is WSS M97B44A. It is Green and requires the FW-16 Conditioner added at intervals during the coolant's lifecycle.
However I can only find compatable Green M97B44A Coolant prefixed with ESE (ESE M97B44A).
Can anyone enlighten me as to what (if any) difference is there between M97B44A Coolant prefixed WSS as opposed to ESE ?? What do the prefixes actually mean??.
Also the last letter can be a different one, A, D etc. What do they mean?

Cheers,
Reg

“Political correctness is a doctrine fostered by and illogical and irrational minority, who hold forth the proposition that it, is entirely possible to pick up a turd by the clean end”