C4 antifreeze

[Frank K.]

Is each year unique to its type of antifreeze? I see Dex Cool as a recommended product to my 1993 LT 1 engine?

[Jim T.]

Re: C4 antifreeze

I am still using the same Dex Cool in my 1996 LT4, been using it since it was new every 5 years.

[Keith B.]

Re: C4 antifreeze

95 or 96 was the first year for Dex Cool. Your 93 defiantly had green

[Frank K.]

Re: C4 antifreeze

It is green&yellow zerex i guess!

[Michael W.]

Re: C4 antifreeze

Coolant colour is meaningless these days, no longer a sure indicator of type or compatibility.

Go by the spec that GM states and make sure any top ups are also the correct spec.

[Duke W.]

Re: C4 antifreeze

95 or 96 was the first year for Dex Cool. Your 93 defiantly had green

I recall it was '96, except Saturn. For prior vehicles that used IAT "green", I recommend HOAT Zerex G-05. Duke

[Joe L.]

Re: C4 antifreeze

Is each year unique to its type of antifreeze? I see Dex Cool as a recommended product to my 1993 LT 1 engine?

Frank------


Here's the "long and short of it":

Corvettes at least through 1994, if not 1995, require a coolant meeting GM spec 1825M. Prestone "yellow/green" and Zerex G-05, among other coolants meet GM spec 1825M. Dex-Cool does not meet GM spec 1825M.

All 1984-96 Corvettes use a heater core which is copper/brass with solder joints. Zerex G-05 is slightly easier on copper/brass and solder than Prestone "yellow/green". You want to do everything possible to postpone the need to replace a C4 heater core for absolutely as long as possible. So, I use Zerex G-05.

A tip for 1996 Corvette owners: The cooling system for 1996 LT1/LT4 is essentially the same as 1992-95 LT1, including a copper brass heater core. While I rarely deviate from GM recommendations, if I had a 1996 Corvette I would not use DexCool. I would use Zerex G-05. Plus, at this point, you don't need to be concerned about warranty requirements.

[Frank K.]

Re: C4 antifreeze

Thanks That heater has never been on! but i did change my C3 core and it was a mess.

[Joe L.]

Re: C4 antifreeze

Frank------

Replacing a C3 heater core is child's play compared to replacing a C4 heater core.

As far as the heater never having been on, that would have little effect on the longevity of the core. Corrosion proceeds inexorably.

[Frank K.]

Re: C4 antifreeze

What can i do to purge it?: Can i bypass it like i did on my 77? I see Ecklers has a item to bypass the constant heat going into the cabin for the 77.