JHZR2
Staff member
Hi,
I have apost about G-05 or G-48 for my 91 BMW below, but I have a question that is more fundamental, so I figure it deserves its own posting.
G-05 is slightly acidic (pH 6.5), and the G-48 is slightly basic(pH 7.2). Does this matter much? This is the concentrate, and so as a result, assuming that you are diluting with Ph7 or so water (water does get acidic in air due to the absorption of carbonate from the air), it seems to me that the pH of the bulk coolant would change anyway, making this somewhat irrelevant...
Also, during use, does not all coolant become acidic??? If the G-05 has a higher reserve alkalinity, shouldnt it stay close to the original pH=6.5 anyway?!?
And, in the end all, looking at the tests from zerex/valvoline, it seems that the G-05 has less corrosion of various metals, as compared to G-48, despite being acidic. The only place it does not do as well is in water pump corrosion, where it geta a '9' after 100 hours, instead of a '10' for the G-48. However, I know that the water pump is original in my 83 MB 300D (as is the radiator and hoses), and it has seen nothing but OE MB coolant, with citric acid flushes (MB - mandated PM) inbetween. Not bad to have a radiator last 23 years and 230k.
What are your thoughts??? Perhaps a weak acid with high reserve alkalinity (buffering capacity, I suppose) is better than slightly basic with less reserve alkalinity (albeit small difference), and poorer corrosion results.
I appreciate your insight! Ths G-05 vs. G-48 is eating me up, and reading the archives has not really calmed my concerns.
Many thanks!
JMH
I have apost about G-05 or G-48 for my 91 BMW below, but I have a question that is more fundamental, so I figure it deserves its own posting.
G-05 is slightly acidic (pH 6.5), and the G-48 is slightly basic(pH 7.2). Does this matter much? This is the concentrate, and so as a result, assuming that you are diluting with Ph7 or so water (water does get acidic in air due to the absorption of carbonate from the air), it seems to me that the pH of the bulk coolant would change anyway, making this somewhat irrelevant...
Also, during use, does not all coolant become acidic??? If the G-05 has a higher reserve alkalinity, shouldnt it stay close to the original pH=6.5 anyway?!?
And, in the end all, looking at the tests from zerex/valvoline, it seems that the G-05 has less corrosion of various metals, as compared to G-48, despite being acidic. The only place it does not do as well is in water pump corrosion, where it geta a '9' after 100 hours, instead of a '10' for the G-48. However, I know that the water pump is original in my 83 MB 300D (as is the radiator and hoses), and it has seen nothing but OE MB coolant, with citric acid flushes (MB - mandated PM) inbetween. Not bad to have a radiator last 23 years and 230k.
What are your thoughts??? Perhaps a weak acid with high reserve alkalinity (buffering capacity, I suppose) is better than slightly basic with less reserve alkalinity (albeit small difference), and poorer corrosion results.
I appreciate your insight! Ths G-05 vs. G-48 is eating me up, and reading the archives has not really calmed my concerns.
Many thanks!
JMH
