Although it does not mention the antifreeze committee, which is made up of engine manufactures as well as antifreeze manufactures with all looking out for the consumer. S48R as a manufacture of antifreeze / coolant belongs and is a voting member of the antifreeze / coolant committee.
Electrolysis and your antifreeze coolant:
If you think the only job of antifreeze (coolant) is to cool the engine during the summer and prevent freeze-up
during the winter, read on. Coolant also plays an important role in preventing corrosion caused by electrolysis. Electrolysis occurs when two dissimilar metals start swapping electrons, causing the metals to corrode. Since an engine has aluminum, copper, cast iron, steel and magnesium alloys, electrolysis will slowly eat away at its innards.
Antifreeze (coolant) has additives to prevent all of that electron swapping. But, as coolant ages, the additives are
depleted and can’t do the job anymore. In fact, worn coolant becomes a pretty darn good electrical conductor,
accelerating internal electrolysis. The good news is that it’s pretty easy to check the conductivity of your coolant with a digital multi-meter. If the conductivity is high, its time for a coolant flush and fill. Here’s a quick way to check it.
Begin with a cold engine. Remove the radiator cap and start the engine. Set your digital multi-meter to DC
volts at 20 volts or less. When it reaches operating temperature, insert the positive probe directly into the coolant. Rev the engine to 2,000 rpm and place the negative probe on the negative battery terminal. If the digital meter reads .4 volts or less, your coolant is in good condition. If it’s greater than .4 volts, the electrolysis additives are exhausted, and you may be in the market for a new radiator, a water pump or a heater core in the future. All of those are far more expensive than a simple coolant change.
1. HD Green With SCA: The antifreeze market is moving away from the “old school” of HD green antifreeze with nitrite (DCA2) and or molybdate (DCA4) as the main inhibitors to measure and boost with DCA as needed. HOWEVER, this can be a viable approach for older mixed-fleets where repairs are an issue.
- What to do: Check nitrite/moly, freeze point, and pH regularly. Add DCA (or spin-on canisters) as required.
- Beware: Older trucks can leak a lot of antifreeze; have jugs of 50/50 available for the drivers to avoid them buying full-strength or simply adding water out of convenience. (S48R conventional +)
2. Nitrited OAT: This is generally the current state of many fleets. Several leading antifreeze blends are a combination of inorganic inhibitors, with a fair share of longer-life organic acids. The “wear indicator” is nitrite, which can deplete rapidly.
- What to do: Check nitrite (dca2) and or moly,(dca4) if applicable, freeze point, and pH regularly. Add DCA2 OR DCA4 extender as required or change filter.
- Beware: OAT coolants are notorious for “weeping” through small fissures and hose barbs. DEFINITELY keep the proper top-off coolant in the trucks. Many convenience stores and truck stops may not have the right product at a reasonable price, and your driver may be forced to compromise the coolant with substandard product. (S48R Extended life global +)
3. Nitrite-free Organic (NAP free): This is the future of truck maintenance, according to the visionaries. One antifreeze / coolant fits all, and can last for 750,000 miles.
- What to do: Check freeze point whenever topping off. Ignore nitrite/moly levels (there are none!). The pH is good down to 6.5! NAP free antifreeze / coolants have significant stop-leak attributes, and you will notice a reduction in coolant loss. Consider marking radiator caps a different color. KEEP NAP FREE FLUID IN THE TRUCKS!
- Beware: Poly organics can tolerate a fair amount of “foreign” coolant, but it will muddy the color and cause your technicians some concern for their spiffy new age antifreeze / coolant (NAP free). (S48R poly ultra +)
4. Mixed Strategy: It is possible to sort the fleet into two groups, and act according to each of the above outlines. Problem: how to designate and not confuse anybody.