While some truck manufacturers are meeting the increased electrical demand with dual alternators, others are turning to big single units, such as the new 24V, 250-amp IdlePro Extreme from Prestolite or the 40 SI series from Delco Remy.
The new alternators are engineered to meet the new challenges inherent in today’s trucks.
The IdlePro has auxiliary draft cooling design prevents high temperature damage and controls front bearing temperature.
The eCoated housing prevents corrosion. The isolated ground technology eliminates stray voltage and protects engines from electrolytic damage. They operate at 76 percent efficiency, producing 90 percent or more of the rated maximum output at engine idle speed.
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Introduced Jan. 31, IdlePro Extreme is termed a heavy-duty replacement alternator, designed for extreme conditions. This is a brushless design intended to increase vehicle uptime and ensure long-lasting battery life, according to Prestolite marketing director Jonathan Smith.
“Like our 12v alternators in the series, this latest entry offers industry-best output at low engine speeds, which is critical for vehicles that spend most of their working lives operating at a low r.p.m. range and powering a high number of electrical draws,” says Smith.
It has dual cable terminals for the installer’s convenience. The company’s designs include the former Leece-Neville and the Motorola lines.
Delco’s 40 SI is another brushless replacement that can add significantly to output and stability.
Rated from 240 to 320 amps, the company says the units are more fuel efficient that OEM units these can replace.
Delco says the units can also improve batter recharge times by up to 50 percent by using a secondary wire from battery to alternator. It continually senses the actual battery voltage and will increase charging voltage to 14 volts immediately if it drops.
These units aren’t light, at more than 30 pounds. They typically have three-year warranties and are designed for long hours of operation.