Hello. I have a 99 Honda Civic Sedan. How often should you replace the engine coolant? I bought the car in Summer 2005 and I haven't changed the coolant since then. I do about 10,000km/year. When should I replace the engine coolant?

 

About every 50K Kilometers or every two years, whichever comes first.

 

I think I'm going to have to replace the engine coolant since I haven't changed it in 4 years. Should I replace it with Honda OEM engine coolant or aftermarket coolant?

 

Aftermarket coolant should be fine.

 

If you have the OEM blue Honda coolant, it only needs to be changed every 90000 according to honda.

 

It has the green coolant right now. Does the green coolant need to be changed every 2 years or every 90,000km?

 

I'd personaly opt for the OEM blue coolant. Aftermarket 'should' be fine...I'm just not a fan of 'should' when I know OEM 'is'.

 

The only aftermarket coolant I would use is the Havoline orange Dexcool. You can get it pre-mixed and pay more, or not pre-mixed and pay less. Walmart, Pep Boys, Checkers, or Autozone should have it. Other aftermarket coolants are said to tend raise the chances of early failure of the water pump, due to incompatibility of the water pump (bearing?) metals and the coolant chemistry. This was also my experience when I used other than OEM or other than the Havoline. I have been using the Havoline orange Dexcool for seven years now (changing every two years, 30k miles per my--and your 99's--owner's manual) and have had no problems. I know some other Honda owners who have also used the Havoline orange Dexcool for years now and think it is as good as the OEM coolant.

Give your Civic's cooling system a good flush, since the coolant is pretty old.

Edit: For non-premixed, use only distilled water.

 

Honda OEM coolant is great stuff and its not really that expensive even, totally worth it to me, I never use anything else in a honda.

 

When you don't use premixed coolant, do you mix the coolant with tap water or distilled water?

 

distilled

 

I imagine tap works fine, wouldn't save much money if you had to get distilled too. I haven't got stuff that isn't premixed in a long time though.

 

lol, never mind, shows how often I use it

 

Distilled water wont have all the calcium and other crap that tap water has. and u DEFINITELY do not want calcium in your cooling system.

 

Alright, good to know, thanks!

 

i wouldnt use tap, lots of **** in there you dont want to be chillin in your system for the next two years.

 

I been using regular water for to dam long now. I keep forgetting to stop and buy some Preston 50/50 Antifreeze. but after reading this that OEM Blue coolant by Honda sounds better. how much for a gallon?

 

I think about $10, but hard to say, I get it discounted, if you were in the milwaukee area I would give you a gallon, lol.