Simanaitis Says

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KENWORTH CELEBRATES a 90th/100th birthday! Lets join in by recalling when Innes Ireland told R&T that he wanted a new Peterbilt, but we got him a Kenworth instead.

Innes Ireland and his Kenworth. This and other photographs by John Lamm for R&T, April 1984.

R&T’s April 1984 road test of a Kenworth W900 Aerodyne was an enlightening adventure for both Innes, the writer, and me, the tester. By the time the dust created by those 18 tires had settled, we both had even more respect for the folks who pilot these big rigs. In fact, the experience also prompted us to order up a special T-shirt for Kenworth test driver Loren Wilhite.

Loren Wilhite, Kenworth test driver, big-rig mentor of Ireland and Simanaitis, 1984. Photo by Pat McQuade.

It was in 1917 that Seattle businessmen Edgar K. Worthington and Captain Frederick Kent bought out the Gerlinger Motor Car Company, to be renamed Kenworth in 1923; thus the dual 90th anniversary in 2013 and 100th anniversary this year. Beginning in 1926, the company added buses to its custom-designed products, another component of its business that exists to this day.

Kenworth history. Thanks to Bill Urban for alerting me to this video.

In 1933, Kenworth was the first American company to offer diesel engines in its vehicles. During World War II, the company built bulkheads and bomb-bay doors for the Boeing B-17 and Consolidated B-24 bombers. By war’s end, Kenworth became part of Pacific Car and Foundry Company, Today’s PACCAR includes Peterbilt as another subsidiary.

As Innes and I learned back in 1984, the buyer of a Kenworth tractor specifies “length of tractor wheelbase, final drive ratio, type and make of engine, suspension layout, etc., as well as the degree of luxury built into the cab and sleeper.”

“In the sleeper itself,” Innes wrote, “with its vee windscreens looking over the cab’s roof there is full standing room with two wide berths, washing facility, loo, fridge, separate air conditioning unit, heater controls and individual courtesy lights as well as hanging space for clothes.”

Innes prepares to work his way through the Kenworth’s 13 forward speeds.

Our Kenworth’s 13-speed gearbox has a hefty shifter arranged in a basic racing 5-speed pattern. Low is over to the left, with the basic other four, labeled 1st through 4th, each having its own Low and High. What’s more, each High has an overdrive, (12 = 4 x 3, plus 1, makes 13).

As Innes noted, “Low is for driving up the side of a house…. These overdrive “splits,” as they’re called, come into play when the driver optimizes fuel economy and speed on varying grades.”

We gathered all these data with the R&T fifth wheel. Or is it a 19th-wheel? Or 20th, given the truckers’ “fifth wheel” term for that plate connecting the tractor to trailer.

The R&T caption reads “Innes catches King of the Hoboes seeking cheap trip to Effingham.” Back in those days, the magazine was printed in this Illinois city.

Our particular W900 Aerodyne was powered by a Cummins diesel, an overhead-valve inline-six displacing 855 cu. in., looking even more imposing at 14,039 cc. It produced 400 hp at a peak 2100 rpm.

Is this enough to propel an as-tested weight of 80,000 lb.? Wrote Innes, “It’s all a matter of gearing, Dennis says, and who am I to doubt him?”

Innes delighted in operating the Kenworth.

In adroitly mastering the intricacies of Kenworth operation, Innes recalled his father’s “serious instruction on double-clutching…. Well I remember how every crunched gear earned me not a verbal reprimand, but a good box on the ear, which probably explains why one side of my head is flatter than the other….”

The R&T At a Glance box compared the Kenworth with its only two other vehicles tested to date that were in any sense comparable: a Greyhound bus and Gresley A3 Pacific locomotive.

The Gresley handled like it was on rails, albeit lethargically. The bus gave the Kenworth a good run for its money, however, as Innes noted, “The Greyhound weighed a piddly 26,667 lb.” ds

© Dennis Simanaitis,, 2017

One comment on “HAPPY 90TH/100TH, KENWORTH TRUCKS

  1. Bill Urban
    May 15, 2017

    Den, thanks to you and Innes for a trip down memory lane. Readers and fellow motorists will be relieved to know all that stressful shifting and double-clutching is fast becoming passé. (Think about the toll this takes on the driver in congested traffic.)
    Automated mechanical transmissions – no clutch pedal – are now included in a significant portion of new truck sales. At Volvo, their 12 speed I-Shift is standard equipment and supplied in 80+% of new sales. It can even learn the topography of each trip and stores the information for future “intelligent cruise-control.”
    And regarding “The Gresley handled like it was on rails, albeit lethargically,” . . . it doesn’t get better than that.

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