Antifreeze ! Whats your poison?

[Frank K.]

What is the best for a C4 cooling system? Are organics preferred?

[Keith B.]

Re: Antifreeze ! Whats your poison?

There is a part number in your owners manual I would go with that or similar

[Larry M.]

Re: Antifreeze ! Whats your poison?

What is the best for a C4 cooling system? Are organics preferred?

If your car started out with DEX-COOL I would probably stay with it. If not, I would use Zerex G-05.

Larry

[Edward J.]

Re: Antifreeze ! Whats your poison?

I agree with Larry, if green anti freeze was used, flush it out and use Zerex G-05.

[John D.]

Re: Antifreeze ! Whats your poison?

From the service bulletin:

SUBJECT: INFORMATION ON PROPYLENE GLYCOL ENGINE COOLANT
MODELS: 1994 AND PRIOR PASSENGER CARS AND TRUCKS

GENERAL MOTORS HAS BEEN REVIEWING DATA SUPPLIED ON THE PERFORMANCE OF PROPYLENE GLYCOL ENGINE COOLANT IN GM VEHICLES. IT IS OUR CONCLUSION THAT PROPYLENE GLYCOL ENGINE COOLANT WILL PERFORM ADEQUATELY UNDER MOST VEHICLE OPERATING CONDITIONS. AS A RESULT, PROPYLENE GLYCOL ENGINE COOLANT (MEETING PERFORMANCE SPECIFICATION GM 1825M) MAY BE USED IN GM VEHICLES AND WILL NOT AFFECT THE WARRANTY COVERAGE.
PRIOR TO ADDING PROPYLENE GLYCOL ENGINE COOLANT TO THE COOLING SYSTEM, ALL THE EXISTING (ETHYLENE GLYCOL) COOLANT MUST BE REMOVED. THIS CAN BE ACCOMPLISHED EITHER BY UTILIZING WATER-BASED COOLANT FLUSHING EQUIPMENT OR "WATERLESS QUICK CHANGE" EQUIPMENT AVAILABLE IN THE GMDE PROGRAM. AS WITH ANY COOLANT CHANGE PROCEDURE, BE SURE TO THOROUGHLY PURGE THE HEATER CORE AND BLOCK AS WELL AS THE RADIATOR BEFORE ATTEMPTING TO CONVERT THE SYSTEM TO PROPYLENE GLYCOL COOLANT.
FREEZE/BOIL POINT LEVELS ARE DIFFERENT FOR PROPYLENE GLYCOL THAN FOR ETHYLENE GLYCOL ENGINE COOLANT. TO ACCURATELY DETERMINE FREEZE/BOIL PROTECTION LEVEL, IT IS IMPERATIVE THAT COOLANTS NOT BE MIXED. REMOVING ALL THE USED COOLANT AS PREVIOUSLY DISCUSSED RESOLVES THIS CONCERN. FREEZE PROTECTION OF PROPYLENE GLYCOL CANNOT BE DETERMINED USING A STANDARD HYDROMETER. RATHER, A REFRACTOMETER OR TEST STRIP MUST BE USED.

[Larry M.]

Re: Antifreeze ! Whats your poison?

From the service bulletin:

SUBJECT: INFORMATION ON PROPYLENE GLYCOL ENGINE COOLANT
MODELS: 1994 AND PRIOR PASSENGER CARS AND TRUCKS

GENERAL MOTORS HAS BEEN REVIEWING DATA SUPPLIED ON THE PERFORMANCE OF PROPYLENE GLYCOL ENGINE COOLANT IN GM VEHICLES. IT IS OUR CONCLUSION THAT PROPYLENE GLYCOL ENGINE COOLANT WILL PERFORM ADEQUATELY UNDER MOST VEHICLE OPERATING CONDITIONS. AS A RESULT, PROPYLENE GLYCOL ENGINE COOLANT (MEETING PERFORMANCE SPECIFICATION GM 1825M) MAY BE USED IN GM VEHICLES AND WILL NOT AFFECT THE WARRANTY COVERAGE.
PRIOR TO ADDING PROPYLENE GLYCOL ENGINE COOLANT TO THE COOLING SYSTEM, ALL THE EXISTING (ETHYLENE GLYCOL) COOLANT MUST BE REMOVED. THIS CAN BE ACCOMPLISHED EITHER BY UTILIZING WATER-BASED COOLANT FLUSHING EQUIPMENT OR "WATERLESS QUICK CHANGE" EQUIPMENT AVAILABLE IN THE GMDE PROGRAM. AS WITH ANY COOLANT CHANGE PROCEDURE, BE SURE TO THOROUGHLY PURGE THE HEATER CORE AND BLOCK AS WELL AS THE RADIATOR BEFORE ATTEMPTING TO CONVERT THE SYSTEM TO PROPYLENE GLYCOL COOLANT.
FREEZE/BOIL POINT LEVELS ARE DIFFERENT FOR PROPYLENE GLYCOL THAN FOR ETHYLENE GLYCOL ENGINE COOLANT. TO ACCURATELY DETERMINE FREEZE/BOIL PROTECTION LEVEL, IT IS IMPERATIVE THAT COOLANTS NOT BE MIXED. REMOVING ALL THE USED COOLANT AS PREVIOUSLY DISCUSSED RESOLVES THIS CONCERN. FREEZE PROTECTION OF PROPYLENE GLYCOL CANNOT BE DETERMINED USING A STANDARD HYDROMETER. RATHER, A REFRACTOMETER OR TEST STRIP MUST BE USED.

But why would I want to change?? Are you concerned about toxicity?? We have been using EG based antifreeze successfully since the early 1960's. That is approx 60 years.

Larry

[Dick W.]

Re: Antifreeze ! Whats your poison?

But why would I want to change?? Are you concerned about toxicity?? We have been using EG based antifreeze successfully since the early 1960's. That is approx 60 years.

Larry

There are problems with ethylene glycol in some applications. IE aluminum/cast iron combination. Solder bloom + many others. EG is a very good coolant when either treated with the proper additives or changed every couple of years.

[Larry M.]

Re: Antifreeze ! Whats your poison?

There are problems with ethylene glycol in some applications. IE aluminum/cast iron combination. Solder bloom + many others. EG is a very good coolant when either treated with the proper additives or changed every couple of years.

I agree..............EG and water provide the freeze protection and boiling protection of the mix. The additives (inorganic, organic, or hybrid) provide the corrosion protection for the metals in your cooling system.

Larry

[Joe L.]

Re: Antifreeze ! Whats your poison?

What is the best for a C4 cooling system? Are organics preferred?

Frank-------


Here's the deal: Technically, any coolant that meets GM specification 1825M is fine. However, consider that the metals in a cooling system in C4 Corvettes is mostly iron and aluminum. The corrosion inhibitors in any 1825M coolant will do very well with these. But, all C4's use a copper/brass heater core with solder joints. Zerex G-05 is somewhat better with copper/brass with solder joints than other coolants and it also meets GM 1825M. With a C4, one should want a heater core to last as long as possible since replacement is an absolute nightmare. So, I say use Zerex G-05.