Which coolant? Green, Dex, Universal?

I am about to get my system flushed. I just wanted to see what you guys would reccommend. It seems the dexcool acts like a ticking -timebomb. Clogging the heatercore eventually. (and other things) I can't say that I have personally seen it, but have read the many issues on numerous other forums. Is it all hype? My car has little miles, but the coolants' age is the change-out factor. I really fear a clogged heater core. Since I already sprung for a $2500 tranny, the car is really like new. I keep cars forever, so I figure now might be a good time to get the older fluid out anyway...

So, here's what I was thinking:

Change to green by going to someone that can use a mechanical pump and flush with straight water till the system is just water. Then, apply green untill about 50/50 mixture. Bleed air. Call it good for two years.

After reading how difficult a cooling system flush CAN be, I figured a $79 bill might be worth it.

Green?
Dexcool?

Tom

I just changed my thermostat and coolant and flushed the system. I had to use a hand pump extractor to get the coolant out of the engine block since I stripped the engine block drain. I figure I got a little over 8 quarts out of the system (10 quarts is the capacity). At least that is the amount I added back into the system. I used Prestone Long Life Coolant (green) that is suppose to be compatible with all coolants on the market. It covers me for 5 yrs/150k miles like Dexcool.

With 166k miles on the odometer, I suspect this will be the last coolant change I do for this car.

Im going to put in the Green stuff dexcool doesn't even last me 2 years it isn't worth it plus it smells like fish and the reservoir is getting some brown stuff. I still have a unknown leak between the front of the engine and the radiator.

No one has proved why green is bad for the LX5 3.5, All I could think is would it eat through the gaskets, come on that can't happen?

yeah definatly avoid dexcool, it sucks. I had dex in my system and I draned about 5L out to change the water pump, then I added some prestone universal yellow supposed to be compatible with all colours of antifreeze. Well now about a year later my resevoir tube it full of brown sludgy stuff and its noticable under the rad cap as well. This is pretty tpyical of dexcool if theres any air in the system. Use the flush kit that you use the garden hose with, crack the rad drain open and crank on the garden hose until it runs clear. close up and fill with either standard green or the univeral yellow at 50/50.

as said before: dexcool and air = bad

= if you change any engine part involving the coolant you should take the dex out.

Engine drain plug is not identified easily = may need to flush the system with water.

When you use the flush kit, I think if memory serves, it wants to be installed in the IN side of the heater core. Which hose is it? (I see a two hoses, mid-engine bay firewall)

Also, what's our radiator's capacity?

Here's an article that gives credence to continue using DexCool:http://free-auto-repair-advice.blogspot.com/search/label/Dex-Cool.
Here is an excerpt which sums up the argument,"Stick with your car maker’s recommendations. Contrary to claims by coolant manufacturers, there is no such thing as a universal replacement coolant...GM’s Dex-Cool is available at most auto parts stores. (I’m not going to get into the discussion about Dex-Cool. There are pros and cons to each argument and I’m simply not convinced that the alleged problems associated with Dex-Cool are caused by Dex-Cool itself. There’s evidence of misuse and defective gasket designs that go way beyond the Dex-Cool issue itself)" As stated in the article many parts of your engine are designed to run with the DexCool, and you run the risk of damage if you use something else. Some issues have occurred while using a "universal coolant" in an engine that previously held DexCool, as you never really get all of the old coolant out no matter how much you flush the engine. The small remaining coolant can mix with the universal coolant and cause problems. I treat my DexCool like the old ethylene glycol coolants of the past and change it out more often than the old recommended 5 yr/150,000 mile mark, and have not had an issue with any of my vehicles that run the DexCool.

I recommend having the dealer power flush the system every 5 years. The aluminium engine can develop scales in the cooling passages which can eventually cause the engine to overheat.

Not on topic, but it is smart to power flush the brake fluid at least every 7 years.

brake fluid sucks up moisture = lines rust and the fluid compresses easier.

If you use the flush kit with the garden hose, you will get all the coolant out as long as you let it run clear. There was also a class action lawsuit against GM for their problems with dexcool. My friend got a letter in the mail for his van, It also covers our cars with the 3.8L...I don't think the 3.5l is covered

http://www.greenflagauto.com/comments.php?catid=1&shownews=322

Ive seen first hand the issues with dexcool, primarily when air is not purged from the system. Mixing dex with green isnt as bad as some may have you think, it simply diminishes dexcools long-life properties. A nice little story about a friend of mine who baught an alero 2 door brand new a few weeks after his parents baught theirs brand new (back in 2003)...the first month he flushed the dexcool and re-filled with green even though it still had a warranty. 2 years later the parents with dexcool lost the intake gasket. warranty covered. Last summer needed a headgasket, warranty not covered. 2 months ago the antifreeze began to leak in the driveway again from the intake gasket...they traded in the car. my friends car never had a problem and still drives it today with green antifreeze. Thats all the convincing I need. Same car,both were baught new, same engine (3.4l) There has never been a prooven problem with green antifreeze, either than being very toxic.

I've heard reports that GM claims that green coolant can eat away aluminum parts in their engines. For the LX5, that could be a huge problem if it's true, as it's basically all aluminum.

Dexcool can also be quite bad for engines/cooling components if it's left in too long or if any air gets into the system, as it reacts to the oxygen and "gunks" up.

Personally, I use dexcool and won't use anything else, but I make sure to change my coolant every 50-60k miles, at least on my Olds. On my newer GM products I don't plan on changing it until 5 yrs or 100-150k miles, as I think they've improved their cooling systems over the years.

The "old standby" green coolant of the past is ethylene glycol. The newer coolants used in modern engines is Organic Acid Technology (or OAT for short) based coolants and have totally different protection packages for the respective engines. The old green coolant should not be used in today's modern engines because of the different metals and alloys that make them up. If you had read the link in my previous post in this thread you would see the damage that could result from using a coolant not designed for today's modern engines...failure of critical water pump and other engine seals.
DexCool is not the problem, rather other factors that influence it such as improper maintenance, the introduction of air into a cooling system rather it be from insufficient bleeding or a faulty radiator cap, and poor gasket and seal designs/materials as has been found out by major redesigns to the gaskets in the past 6 years.
Yeah there are class action lawsuits out there, mainly started by greedy law firms who specialize in making their money off of such cases by advertising it trying to get more clients. Most class action suit do not reward the plaintiffs with a high settlement amount because the bulk of the award (if any) are gobbled up by the lawyer's fees.:shakehead:
I've seen engines dismantled that ran either DexCool or some other non-OAT coolant and while the damage may not present itself in the near future, it manifests itself over time causing a great deal of internal damage to those engines not running the DexCool. Properly maintaining your cooling system by flushing and refilling every 3 yrs or 36 to 50,000 miles, bleeding all the air out of the system, and making sure the radiator cap is in proper working order can go a long way in ensuring a trouble free system. I follow those guidelines and have not had problems in any of the vehicles I own that have used DexCool.

I agree. Dex cool is OK as long as proper maintenance is done, including properly purging the air. Also, GM's biggest mistake was making it a 240,000km change intervall for the coolant. That is bound to cause corrosion/sludge issues if left that long. In fact after the 2000 model year they changed the coolant service intervalls. Personally I run HOAT, the universal 'hybrid' OAT stuff.

^^ and flush the system every few years/50-60k miles regardless of what type antifreeze is in your car..