LS1 cooling system
 

My car is 5 years old now and the manual says the coolant should be changed every 5 years or 150,000 miles whichever comes first. Is that gospel, or could I let go a little a longer? My car has 32,000 miles on it right now.

Id say do it. it cant hurt, ive seen on ls1tech the guys say its good if maintained properly. my car had 64k, and i had to change it when i did the new motor. It was horrible looking. i cant stand dex-cool. i drained everything except the heater core and put it the prestone green "any make any color" stuff.

How did it go when you backflushed it? Is there a good kit for the LS1 or will any do?

i didnt have to really flush anything in my case. im not sure how others do it, im sure they explain it on ls1tech, i just hate that site because everyone thinks they know better.

I had a new brand motor, all new hoses and i flushed the rad with a hose while it was out of the car. once everything was dry again and clean, then it got reinstalled. I even removed and flushed my overflow tank and got a ton of sludge junk out of it. Also when i filled it, i did an exact 50/50 mix of coolant and distilled water.

I have the service manual...it gives the steps for draining the system, but when it comes to flushing it just says to buy a kit and follow its instructions...so I'm guessing it's just like any other motor.

If you have Dex-Cool and it has even a hint of brown in it, flush it now and replace it with Peak Global.

In my GTP I had 'jerky' build up from dex cool- and by that I mean I had congealed pieces of dex cool in my system that came out like strips of beef jerky.

Yeah, I had gunk like that in my '97 Sunfire. I never buy Dex-Cool, just something that says it meets spec of GM engines with Dex-Cool.

When i fill systems, i mix a/f with distilled water - supposed to be better then tap water (minerals and such , IIRC)

less corosive as well... i did mine around 40k to be on the safe side. i'm gonna have to do it again since my radiator is out and i will be using prestone green again