Chrysler says the coolant is good for 100k. I did mine around 80k. The way i see it, it costs less the $50.00 in materials and less then 2 hours of time. Ill just do it every 80k miles. Test strips would be nice. But if you are changing it when you are supposed to i see no need for them.

 

greg what do you mean burp it thanks

 

Test strips are just ordinary litmus paper to test for PH. You can use any ones you get your hands on.

Normal coolant PH is from 8.5 to 10.5. Values above 11.5 will corrode aluminum and contribute to scale. There is some variation in the recommended PH value to change coolant; some say anything below 8.0; others suggest 7.0 and even 6.5. You decide.

You can also test coolant with a Volt-Ohm Meter (VOM). You put one probe on the negative battery terminal and the other into the coolant; best if you're careful not to touch other metal with the second probe when you're placing it in the coolant. Have the ignition off and the key out of the ignition switch.

You will see different thresholds for voltage on the net but I use the numbers supplied by an oil and coolant analysis company. They are lower (more conservative) than most.

0.0 to 0.3V normal in a gasoline engine
0.3 to 0.5V will cause problems if left in an iron block
0.15 to 0.5V will cause problems if left in an aluminum block

I'm not convinced the voltage test is a good idea if you are just deciding if the coolant needs replacing. The act of testing the coolant this way will kill any iron-supressing additives in the coolant. There are a bunch more tests you could do with this probe/coolant method, checking for various electrical ground issues. Just in case anyone is interested.

Although most people are led to believe otherwise, pure water will not conduct any electrical current. However if you introduce any contaminants into water ...suspended dust is more than enough ... it then will conduct electricity. You don't hear the first part because wet environments are a safety hazard for electrical shock, and safety ****'s would rather tell you a half-truth that will save your butt than the whole truth, on the assumption we're all morons and won't be able to figure it out.

You could perform the coolant voltage test if you are in the process of changing the coolant, as a benchmark for future change interval decisions or ongoing maintenance records. Since you're changing the coolant anyway, the loss of iron suppressants won't be detrimental to the engine.

You can also do a coolant analysis; the same companies that do fleet oil analysis can perform the test. It's not cheap but I suppose if you do your coolant maintenance yourself it won't end up being more expensive to buy the antifreeze, maybe a flush compound, and have the analysis done, as taking it in to a dealer to swap the coolant would cost.

Polaris Labs will do them. If you decide to go that route, it's cheaper to buy the test kits from them in 10-packs than singles by quite a bit. Maybe people could get together on a 10-pack. A lot of guys like Blackstone Labs for oil analysis; I don't think they do coolant though. Personally I don't see the need for coolant analysis unless you've got a fleet to maintain or want to get big miles out of a diesel, but you never know, you might learn something about the engine. The level 1 Polaris Coolant test you could almost do yourself with the PH strips and the VOM, so I don't think it's worth it myself.

http://www.polarislabs.com US lab
http://www.polarislabs.ca Canada lab
http://www.blackstone-labs.com Oil only

 

I just stumbled across this thread, and now I'm wondering, does my 2002 Ram 4.7L require HOAT coolant? because I don't think that's what's in it and I've been topping it off with premixed stuff until I can find my leak.

so when I do a flush should I be buying the HOAT coolant to fill it back up again?

 

Yes, you absolutely should use HOAT.

 

Is there a brand that can be bought or does it come strictly from the dealer?

 

it says earlier in the post, valvoline zerex G-05.

 

Yes sir, Valvoline Zerex G-05.