I know there are several threads concerning which color/type coolant to use, but has any one ever seen a dark colored coolant? I've checked the level by looking at the bottle only long enough to see it was at the normal mark, but I never really looked at it. Opened the bottle and the coolant is a dark brown. Not having any problems with cooling but I&quot;ve never seen this before and it kind of bothered me. <br><br>Is this normal? Could it be stock coolant that has not been changed in the 60k miles on the truck? <br><br>thanks, Roy

 

Darkest I've seen is a dark red coolant, but only in Mercedes. Brown sounds bad. Is it transparent or cloudy? If cloudy I don't think it's supposed to be that way. You might want to consider a flush and refill of a known color coolant.<br><br>Chris

 

sounds kinda like a mix of 2 different types together.....<br><br>ive seen dexcool and regular antifreeze mixed together before and it sorta looks like what ur describing<br><br>

 

<br> Have seen coolant turn dark brown because of the radiator not being grounded to the chassis! BIG MIKE

 

Haven't looked yet, just got a chance to read the forum. Is there a ground strap on the radiator or is it grounded through the mounting bolts?

 

Standard green coolant when Bars Leaks is added, it turns brown. Bars Leaks is standard in many vehicles and motorcycles from the factory, so many mechanics add it to all antifreez changes.