Originally Posted by tempforce

the freeze 12 will cool better than r134a. duracool is better yet..

have the system pumped down and change the schrader valve and dryer. fill with nitrogen and check for leaks.. let it blow down/vent. pump the system down and fill with the correct amount of r-12/freeze/dura-cool. charts are available for the alternate coolants… the dura-cool charge is less than r-12 and cools better… the freeze is in between the r-12 and r-134a..
if you change to r-134a, you need to flush the entire system, replace the dryer and add the required lube oil. don't expect the system to cool very well.. as the r-134a systems are designed with a larger condenser and compresser. they are designed to run at higher pressures, as well…