Antifreeze goop

[toupee]

Hi all,
I checked the antifreeze in my daily driver and noticed a brownish/red waxy/pasty deposit on the dipstick.  I'm guessing this is the result of some long term chemical reaction.  The coolant is Dexcool, if that matters.  Can someone elaborate?

[resq302]

What kind of car do you have that you coolant tank has a dipstick?  Every coolant tank that I have seen has a cap with no dipstick.

[toupee]

  OK, no flaming now- an 06 Pontiac GTO.  Like I said, it's my driver - I still have my old mopar so I am not a traitor.  Besides, it's a nice car.  .

PS It's a plastic dipstick in a little side reservoir off to the side of the main radiator/radiator cap.

[resq302]

Im still confused.  Are you referring to the little "window" that you can see through on the overflow bottle?

[GreenMachine]

I thought GM ditched Dexcool?

   I believe that paste is rust and it WILL cause problems. You need to flush your system. I've never had a shop do it before, so I don't know what they use or how effective it is. I've used the Prestone flush on a Chevy truck that had the same problem as yours, it took about 3 or 4 flushes before the water stayed clear. Afterwards, I'd fill it back up with the green Prestone. 

[toupee]

I had a fellow goat owner tell me that it is stop leak and GM put it in all ls2 engines.  Supposedly GM puts in it LS3 engines as well for some unknown reason. 

[y3chargerrt]

Umm beacuse they suck??

[maxwellwedge]

I heard the same thing about the stop-leak stuff. Dexcool was the best thing ever years ago and now it's death....get it out of there. This goes for anyone using it in your Mopars too. Change your anti-freeze yearly to avoid big problems!!!!!!! It will eat frost plugs (and worse) if it turns acid.

[resq302]

I agree.  It ate the rubber intake gasket on my grandmothers 2000 Buick Century and even did damage to the seals of the water pump.  GM rep claims that once air was introduced to the system the coolant goes bad.  To my knowledge, the over flow tank always has air in the system since it is not filled up to the brim.  GM doesn't make sense sometimes.

[toupee]

GM doesn't make sense sometimes.

I think that's true of all car manufacturers.