As mentioned in an article last month, I have been helping out friends by driving a 10-speed triaxle dump truck (6AM to 6PM) 2 to 3 days a week this summer.
Using older but well-maintained dump trucks and newer state-of-the-art excavation equipment, six guys working full-time, plus me helping out part-time, are removing the concrete on a stretch of road and several streets in a small town located in an adjacent county. Additionally, we are coordinating with two road engineers, and conferring with local utility employees overseeing the project. Our crew is handling the overall excavation, installation of underground drainage infrastructure, dumping the old concrete in designated land areas, hauling away dirt to two other locations, and hauling in rock from two separate quarries. All of this is being done in advance of a paving company’s final pouring of the concrete.
In some ways, excavating pavement is like a war: It is a daily grindfest whereby demolition is ongoing and progress takes time. Our crew consists of an onsite Colonel, so to speak, who operates the big machines and confers with the engineers and local employees, a Captain acting as the site supervisor, a Sergeant who musters the crew and drives a dump truck as needed, two grunts who can also operate skid-steers, end-loaders, backhoes, rollers, and graders, plus myself and another driver who are hauling and dumping non-stop all day.
The General of the company is my age and oversees the operations of his other businesses from the main headquarters. His son is the Colonel in charge of excavation and works closely with the engineers and the local city and county employees. The Captain is 20 years younger than me but, given his career under the sun, he looks only about 10 years younger. He is an experienced site supervisor but has been with this company for only about one month. The Sergeant is in his upper 20s. He is a decent mechanic and well-rounded equipment operator and overall “go to” guy. The grunts are 22 and 18 years old and, like the sergeant, have been employed by this excavation company for all of three weeks; about as long as me.
Although it has been years since I drove a 10-speed truck, and in spite of never having driven a Mack dump truck before, it has been going well. To spare my left knee from double-clutching all day (clutching to neutral then clutching again into gear), which is required for a non-synchronizedtransmission, I have been “floating gears” instead. This is a method of bypassing the clutch and aligning the engine speed (RPMs) and vehicle speed to the exact gears at the right time.
An Eaton Fuller 10-speed transmission is basically a low-range 5-speed manual transmission beneath a high-range 5-speed. The low and high ranges are separated by a “range selector” (or splitter) button on the stick shift.
For those who are interested, the below video shows what it’s like to align the RPMs, vehicle speed, and gears in a 10-speed truck.
The upshifting begins at: 15 seconds and the downshifting begins at the 1:56 mark.
Notice a couple of things:
– When upshifting a fully loaded truck, the transmission is usually shifted through six gears before a speed of 15 MPH is reached. This is about the amount of time required to cross an intersection from a full stop at a stoplight