: Just bought my first Cadillac-Has green coolant

05-28-06, 08:59 AM
I just bought a 97 Seville SLS for $2800. Thanks to this forum, I knew how to read the codes and check things out before deciding to buy. Only code was for the catalyst and it obviousy has a bad catalytic converter. So i found the magnaflow cat for $117 and will be replacing it. I was planning on changing all the fluids just to cover all the bases and I noticed that it has green coolant. So some idiot changed it with regular antifreeze. I know from the forum that it needs the Dexcool and also some Bars Leak in the lower radiator hose. Can you guys tell me the best way to make sure and get all the old coolant out? On other cars I have kept water running into the radiator with the upper hose off until it ran clear. Obviously I cant do it that way since there is no cap on the radiator.

05-28-06, 09:15 AM
The easiest way to drain is to pull the lower hose. And no, you will not get all the coolant out of there. Put the coolant supplement in the lower hose before you put it all back together.

You will have to use a two year / 24,000 mile cycle on your coolant now that green EG has been used. And there is no need to use Dex-Cool, but you can if you want to; be sure to observe the two year cycle no matter what type of EG you use.

05-28-06, 09:21 AM
Well that kind of sucks, but OK. I didnt realize that once you put the green in that you are stuck with it. I guess I will just have to change it again a little sooner. Thanks JimD. As far as the transmission goes, is it good enough just to drain the pan, and a new filter?

05-28-06, 10:37 AM
JimD is exactly right on the coolant.

Yes, drain the ATF. There is a plug (10mm I think) that will be exposed once the filter is off. That drains the upper sump of the trans. You'll get more out that way. The filter should be reuseable if it is the metal screen. The gasket is reuseable if it is the factory rubber gasket.

05-28-06, 11:01 AM
also do not flush your rad and your tranny drain and fill ONLY flushing is BAD!!!

05-28-06, 05:05 PM
Yes, and what ever you do, never take it to the dealer for this service. I did and it cost me a transmission. They flushed it and didn't change the filters, after I told them to simply drain it, and replace the filters afterwards. I would also recommend not driving it before you do the tranny work if you can help it. I didn't have a choice when I did my filters, and had to change it after class (I had just gone out to eat lunch less thna an hour before hand). Getting drenched it hot tranny fluid is not fun. Good luck.

05-28-06, 06:33 PM
Thanks for all the advice guys. I will be doing the work tomorrow, so hopfully everything will go smoothly.