1990 DT466 coolant question

[BusDreamerRick]

Hi everyone!
I’m trying to figure out what type of coolant to put into my Dt466 engine. I’ve looked elsewhere for manuals but it’s only post 1993 mine is a 1990
I lost a bit of coolant when I removed the heater, and I’m looking to top it off, I just don’t know with what. Should I just go with what’s already in there which is green coolant as long as it reads Navistar* B1 type 1?
Also what are you guys using in your DT466? I read the Peak fleetcharge stuff is great, is it worth flushing and refilling it with that instead of what I have even though it’s pink? Also, I understand that these green coolant engines need additives to prevent cavitation which would you recommend? I’ve been at this for weeks and I ask the people at Napa and they look at me weird asking them about coolant additives and PH testing strips. -_____-

My bus specs are 1990 International 3800 w/DT466 with MD436 tranny. I love this bus and I want to have it as up to spec as possible, but I don’t want to break it with a dumb move like putting in the wrong coolant.

I hope I was as detailed as possible, thanks in advance you guys!

[PorchDog]

I would use the old style green coolant. I have a 1996 DT466 and it has what folks call a "coolant filter" mounted near the water pump. Buy some coolant test strips and check your coolant for the nitrite level. Use Green coolant and change the filter if the coolant strips show low nitrite levels.

My personal opinion is that the o-rings on the cylinder liners of the older engines may not be completely compatible with the new coolants-- and if it has had green in it all these years-- why risk changing to the newer stuff?

[s2mikon]

As above. Use green coolant and use test strips. Wix sells the test strips and also the coolant additive. It is very easy to do.