Originally Posted by Drawbar

This seemed to be the best thread to use. I just want to top up my coolant res. It has factory Blue in there and has about an 1-11/4 inch of the rib level showing. I purchased the Mopar MS 9769 that the TSB's say you can use "in lieu of", and of course can't mix it with "green" regular coolant. Sounds a little bit of overkill question, but can I use this coolant to top it up, or does in lieu of mean if I were to "replace" the coolant, in which case I need the Benz Blue for top up? Thanks, 2004 Silver Blue 6spd Coupe. Annnnd......Loving it!