I just received my Griffin radiator 1-55241-T. (Making a feeble attempt at doing the stand up radiator mod with a/c condenser) The rep at Griffin told me I could only use the green coolant in it. I thought the LS motors could only run the orange stuff. My brother is telling me to use the yellow one. So now I don't know what to use.

Help!

 

I flushed all the Dexcool crap out of mine, as long as you get rid of all the red stuff you can run the green stuff no problem.

 

Do A LOT of flushing, you can use tap water for this, flush until you are sick of flushing. Get ALL the old coolant out of there.

Then, fill with distilled water, 100% distilled, then flush that out without another round of 100% distilled, then again 100% distilled. When you are SURE that all the tap water is gone, and nothing is left except distilled water, THEN you can drain however much distilled you want to put in however much green coolant you want. In FL I run 10% green 90% distilled, it never freezes here. Distilled water is better than coolant for actually controlling temperature so use as much as you can. Its also cheaper and safer for the environment and you can drink it!

Main thing is: Make sure no traces of the old coolant, OR any tap water is left, before you finally cap the system off for good.

 

I used a chemical flush and about 4 tap water flushes. After this I filled it with a mix of distilled water and another bottle of chemical flush. After that I did a distilled water flush, and then drained it one last time and filled it with 50% green stuff and 50% distilled water. It was a long day. Be sure to turn your heat on to flush out the heater core too!

 

Thanks guys!

 

Quick ? I have a 6.0 I'm putting in 94 Chevy c1500 truck. What kind of radiator do I need?

 

I used to believe all the "dexcool gums up when exposed to oxygen" and **** like that stories.

I was told when GM originally contracted Havoline there was a problem with some of the inhibitors being incompatible with certain gasket materials causing failures and gumming up. The other explanation I heard was a system running low for extended periods of time causes rust from block, heads and other engine components, and the sludge is actually rust.

Dexcool is a OAT coolant, almost all manufacturers have switched to something similar, some use different inhibitors, but its pretty much all based on the same stuff.

I used to care and switched my Z71 but it was a pain in the ***, so I didnt switch the Z28 and after putting 100K miles on it to a total of 200K I never had a coolant gumming issue.

Also run both my dodges on dexcool, they call for a zerex coolant or something, which is an OAT with different or no inhibitors (I cant remeber), but I can get dexcool at the parts house, both have over 300K miles with one soon approaching 400K miles, and no coolant gumming issues.

As far as Im concerned the Dexcool problem is long over, unless you rocking a 90s northstar or 3.4 or whatever they had problems in, but Id put it in any of my cars and do and have never had problems. Switching is an unnecessary pain in the ***

Edit: if a manufacturer told you to switch to green then Id consider it so if there is a problem they dont have an out to deny warrantying parts, but for stock stuff, i wouldnt consider switching. I would ask them why they recommend green coolant though

 

Another z71 & z28 owner! I only switched to the green because they had problems with the 3.4 and 3800s which I've had both and had to switch. It was pretty much just a habit. I know people who swear by the Dex cool stuff and I may actually switch back over after my head swap.

 

X2^^^

Never had a problem with Dex in the LS motors, service the cooling system every 100,000 miles or so and you'll be fine. I wouldn't waste the time flushing the system to switch to green but that's my $.02