hello guys, i have a 2002 3.8 camaro 5 speed and this summer i want to do a coolant flush with a kit im going to buy from walmart. i have heard so many things regarding the gm dexcool stuff. i have heard that the stuff is fine because they are still useing it in all the new models. then other people say the stuff is complete garbage and to stop useing it. i was just about to switch coolants when i read a post that switching coolants can be bad to??? can anybody shed some light on my situation?!?

 

Dexcool=needed in your car..green ****=sludge in your car. Dex is what your car calls for..outside of my car ive always used green..but you need dexcool in these cars

 

Eh, I've heard both sides of the story, too. I've read about how Dex-cool ruins the car (it causes the sludge build-up and stuff to 'rot' through) and I've read that the regular stuff causes build-up. A LOT of people have written complaints about how Dex-cool has caused a lot of problems for them. When I got my car, it had some build-up in it, (the coolant was green), and it had a crack in the radiator. I had a shop replace the radiator and all the hoses and they filled it with some sort of green coolant. As far as I know, Dex-cool comes in the red/orange and green? So I don't even know what's being ran in it now (Dex-cool or not), but I do know there's no build-up....yet...
so from what I've read (and like what you've said), it's been a 50/50 split between Dex-cool being good and bad...it still confuses me.

 

yea i want to do a coolant flush just to flush all the crap out, how often do u guys/girls recomend changing the fluid and doing a fluid flush?

 

Truth of the matter is as long as you maintain the coolant like you are supposed to neither are a problem. The older style coolants will form acids in as little as 2 1/2 years. Once this reaction starts you need to neutralize it (most flush preps do this). Add clean fluid to old fluid will not fix it.
The Dex-Cool will gunk up. It turns into sludge. Both will screw up your motor but the Dex is easy to spot. It will cause over heating due to a lack of flow. The older stuff will keep you motor cool but it will show up as water pumps failing blown head gaskets even alumi intakes being eaten away. It will eat away at the rad and cause the passages to block off but that is after years of neglect.

All this can be avoided by changing your Antifreeze every 2 years. With the exception of brake fluid it is the most over look maintenance on a car.

 

Whichever you choose, there are a few things that you definitely DO NOT want to do:

DO NOT use ethylene glycol based coolant. It can deteriorate the aluminum in your engine.

DO NOT mix coolant types, even if they say they can be "added to any color antifreeze." This is the most common reason for the buildup of "sludge" that you guys were mentioning.

A few good DOs:

DO know what's in your engine, so you always know what to add if you run short.

DO perform a comlpete flush if you plan on swapping, because mixing coolant types causes its own problems.

DO use either Dex-Cool (usually red or orange) OR any propylene glycol based coolant (usually green or yellow). Either of these are okay in aluminum engines as long as you dont' mix them.

A little bit of info about Dex-Cool... This was created by GM because the old ethylene glycol stuff had a tendency to make the aluminum rust and deteriorate, which both clogged the coolant pathways and shredded the engine. Dex-Cool supposedly lasts longer than ethylene- or propylene-glycol coolants, but this is one reason people complain of Dex-Cool causing sludge. If it's left in too long, or if the engine use is rough, the stuff will sludge up.

Also, if you ever get your oil changed somewhere and they "top off your fluids," they will probably mix the other stuff in and get you sludged up that way. The flipside of that is that if you put in propylene glycol and take it to someone who knows these cars use Dex-Cool, they'll put in the Dex-Cool and sludge things up that way. Always let your mechanics know what's in your car.

Propylene glycol doesn't last as long as Dex-Cool supposedly does, but in my personal experience it does a better job of cooling the engine. It's also a thinner fluid to begin with, so it will flow a little faster. I use this stuff in my '96 3.8L, and I haven't had any sludge since I swapped to this type (I did when I used Dex-Cool, but that was probably caused more by other coolant problems, like leaks, that I had at that time).

 

So, can regular coolant look like gunked up Dex-cool towards the end of that 2-2 1/2 year term? My radiator cap looked like a rust color with some gunk on it, was that from Dex-cool?

 

Any coolant will gunk up if it's been in there too long. If your rad cap looks like rusty gunk, it's probably past time to flush/refill.

 

It doesn't now, before I had my whole radiator and everything replaced it did. Just wondering for future reference.

 

ok thanks guys!! so would the prestone 50/50 dexcool stuff from walmart be ok to use in my car? also do u guys know how big the capasity of the cooling system is for a 2002 with a 3.8?