UltraShift Shootout
Can automatic transmissions level the field between good and bad drivers?
Steve Sturgess
Executive Editor
The idea was great. The plan was to drive Eaton's UltraShift 13-speed LEP in a competitive situation to show how the automated shifting transmission could level the playing field between good and bad drivers.
Because Jim Park, editor of our Canadian sister journal, Highway Star, and I have been sparring over fuel economy all year, we were invited to see if we could beat John Chrapek, the incumbent fuel economy champion at our host carrier, Mackie Moving Systems, based in Oshawa, Ontario.
So on a blustery October day, the three of us took turns driving three different trucks over a 31-mile route on the east side of Toronto. The plan was to record the fuel used by reading from the engine ECUs, then verify the total fuel used by refilling the tanks at the end of the day. Unfortunately, Mackie fleet manager Derek Varley's computer had been stolen only days earlier, and we had no way to unlock the ECUs. This meant we had to top-off after every test to calculate mpgs. Thirty miles is not really far enough to get repeatable fuel economy data that would cover the sort of differences we were trying to measure.
Or maybe it's just sour grapes, because Mackie's Chrapek was the runaway winner on all three trucks. Jim Park outdid me on the automated truck, but I got him on the manual.
The trucks lined up for us that morning were an International 9400i with the Eaton UltraShift LEP with a Cummins ISX 450, loaded to 65,000 pounds; an International 4300 Class 6 with six-speed UltraShift, also loaded; and as a control, a Peterbilt 379 daycab belonging to Mackie, with the same power and 3.55 rear end ratios as the International, but a 10-speed manual transmission. Originally, we had intended the Mackie truck be loaded to provide a comparison with the UltraShift but, in line with the other problems that day, it didn't happen.
Chrapek led off in the medium-duty on the first circuit, which took in freeway, some stop-and-go urban streets and rural two-lane roads. I followed in the UltraShift 9400i and, flailing away at the gearlever, Park had the back door.
Filling up after the first run, Chrapek had bettered 11 mpg. I came in at 4.4 mpg with the automated International, and Park astounded us all with 5.53 mpg. It was at this point that we found out the Mackie truck wasn't loaded, narrowly saving Eaton public relations representative Mike O'Neill from killing himself.
We switched seats for the next run, with Chrapek in the UltraShift 9400i, Park in the 4300 and me in the gearjammer Peterbilt. This time I beat Park's fuel economy in the 10-speed, he struggled with the automated six-speed medium and Chrapek posted 5.2 mpg in the big International. That would turn out to be the best of the day for the LEP-equipped 9400i.
Round three, and Park got his shot at the 9400i, Chrapek drove the manual Pete and I got to play with the little 4300. At the end of the day, Park bettered me in the automated big truck with 4.8 mpg, and I bettered him with the straight truck by a few tenths.
I puzzled over the fact that Park had beaten me in the automated 9400i. I had driven the truck with a lot of intervention, deliberately calling for early upshifts by punching the shifter button on the console. The normal shift point is around 1,500 rpm, a point I'd never approach even in the high side of the transmission. So I reasoned that if I could keep the rpms low I'd beat Park.
We talked about my strategy versus Park's of letting the auto do its own thing. (We also discussed the fact that I had run slowly, holding up Park in the first test. This I denied, but I did stay at or below posted limits, while Park, a former owner-operator, maintains you can't do that and get the job done.)
The conclusion we came to is that the Cummins likes to run between its peak torque and peak power rpms, and that by upshifting early I was forcing it to run on the early upswing of the specific fuel curve.
The automated International was a breeze to drive, and I had plenty of time to look at the Canadian countryside. Stops and starts were simple, though I complicated them by poking at the manual selector and punching the upshift button. It did no good and only served to make me a mite less safe.
That's the beauty of the automated transmission. Along with allowing the less experienced or less conscientious driver to get comparable fuel mileage to top drivers such as Mackie's Chrapek, taking away the shifting task gives the driver more time to concentrate on traffic.
So, while the results didn't come out the way I wanted, the exercise was still very worthwhile.
