Fully formulated coolant is a 50/50 mixture of ethylene glycol and water.
The ConcreteSock fits over the end of a ready-mix truck's chute to prevent concrete from spilling onto roadways.

The engine will run well on waterless coolant, but to take full advantage, you can make a few modifications. First, change the thermostat from your current 180 or 190 degrees F to 215 degrees F. Then have your engine dealer raise the fan-on temperature to 230 degrees F. You can also add a ResistorPac from Evans in series with the temperature sensor. It will raise the fan-on temperature and elevate the derating overheat protection temperature. Check with Evans or your dealer for the correct ohm rating for your engine.

If ordering a new truck, specify Evans waterless coolant, a 205 degrees F thermostat, and ECM programming set to provide fan-on at 230 degrees F, fan-off at 217 degrees F, de-rating at 235 degrees F and auto-shutdown at 240 degrees F.

In SAE Type II fuel consumption tests (J1321) conducted by Auburn University's PAVE Research Center, fuel economy improvements exceeded 3%, primarily due to reduced fan-on time.


There are downsides to switching to waterless coolant. One factor is availability. This is more important for pre-cast haulers traveling great distances than for ready-mix trucks. If you have a slow leak, you may be able to limp home on the gallon or two you should carry with you. But if something catastrophic like a burst radiator or heater hose happens, you can't just repair it and replace with ordinary coolant.

You will need to find a service provider that carries Evans' coolant. If you just add water, you lose all the benefits of your expensive changeover. It's a small risk, but a risk nonetheless.

Expense is another major factor. Evans coolant costs over $40 per gallon. With big bore diesels that have coolant capacities of 70 or 80 quarts (17.5 to 20 gal), coolant alone can run $700 to $800 per truck. The justification is in fuel economy, savings in maintenance supplies and labor, and reduced wear and tear on the cooling system.

Paul Abelson is a former director of the Technology and Maintenance Council of the American Trucking Associations and is on the board of the Truck Writers of North America. E-mail

Put a Sock in It

A sure way to aggravate a motorist is to dribble wet concrete from the rear of a ready-mix truck onto his vehicle. An English company has developed a way to prevent unnecessary damage claims.

The ConcreteSock is a durable cover which goes over the end of the chute to keep concrete from falling out during the trip back to the plant. In England, Cornwall Ready Mix has mandated using the product for its entire fleet. The producer has noticed a significant reduction in calls about chipped windshields and damaged paint. The chute cover, which takes 10 to 30 seconds to install, may be especially useful where washout facilities are limited like in congested downtown areas.

The ConcreteSock, which costs about $400, is available in a number of different designs to securely fit different chutes. It is not yet available in the U.S., although the developer is seeking a U.S. partner, having already secured provisional patent protection here. For more information, visit