No backing down
At less than 5 mph, active regeneration stops and resumes only when the truck speeds up again. This feature prevents the potentially high heat created by regeneration from damaging trailers or anything else that might be close to the exhaust discharge, Tindall says. Our test truck had thousands of miles on it accumulated at city and highway speeds, and our trailer had no signs of heat damage even just behind the exhaust discharge.
Tindall’s technician started the active regeneration cycle about a third of the way through the test drive. A computer screen mounted on the dashboard showed the input and output temperatures inside the DPF. At idle the temperatures are at about 170 degrees, normal running temperatures are about 446 degrees, and during active regeneration, temperatures inside the DPF got up to about 1,100 degrees.
When we slowed to 30 mph and or came to a stop, the illuminated dash warning light indicated regeneration was in progress. But otherwise I wouldn’t have known because the process did not affect the S60′s performance.
A more comprehensive test drive including long interrupted stretches at highway speeds and seriously challenging hills will tell more. As well, the jury won’t reach accurate verdicts on any ’07 engines until they’ve been on the market for a year or so.
But our two-hour, 75-mile jaunt across rainy, cloudy Southern Michigan was comprehensive enough to determine that DD’s 2007 S60 sacrifices no performance or efficiency.
SPEC’S AS TESTED
Engine: 2007 Detroit Diesel Series 60
Displacement: 14 liters
Horsepower: 455 at 1,800 rpm
Torque: 1550 foot-pounds at 1,250 rpm
Compression ratio: 17:1
Rear Differential: Queried
Wheels/Tires: 295/75 R22.5
Transmission: Eaton Ultrashift 10-speed automatic
Fuel: Ultra low-sulfur diesel
Gross Vehicle Weight: Approximately 80,000 pounds
Test drive length: 75 miles