[Richard and Rhonda]

Tuga,

I use the Donaldson P552088 Coolant Filter http://www.donaldson.com/en/engine/s...ary/000376.pdf

It has kept my numbers right where they should be.

You are using the standard green coolant, correct. Because if you have switched over the the red or orange long life stuff, it uses different chemistry. Although both are ethylene glycol, the additive packages are completely different, and most importantly incompatible.