The either start installed on these trucks is a measured dose and has been used for many many years on these trucks and never has there been a publication of any problems with its use in the military, And they are safe for long term use, your truck has had them used on it a bunch of times before. opinions are fine and worth allot to those who have em , Bkubu has the insight and experience to know, Like he said, If no block heater plug in at the winter show use the either start on board or a splash of either in the air intake the truck, thats what it is for and it works, As for the 809 series, the correct cold start procedure works very very well for that truck also. Now there is a bazzzillion and "one" posts on this subject
The search function actually answers more questions than just the first one that comes to mind, There are picks of the block heater in the block , part numbers, places to buy them. one will find so much more when searching, All the best . Oh the either start on the truck runs out when needed most, carry a can also in the tool box.