One of the visual traits most folks admire about a vintage truck is its stark simplicity of design. Compared to old cars there's not near as many things going on in the bells-and-whistles department. In a decade-by-decade comparison, older automobiles were usually way ahead of light-duty trucks with a plethora of standard and optional gizmos accentuated with chrome-plated embellishments. In direct contrast, it's interesting to note that when the criteria is singled down to instrumentation, the truck-versus-car comparo goes right out the window.
Look at any dashboard on a '50s through '60s Buick, Cadillac, or Oldsmobile, and there's not one analog gauge to monitor oil pressure, water temperature, or 12-volt charging-it was all done with idiot lights. Having to wait for an idiot light to come on in a '50s truck when something like the oil pressure or charging system was getting ready to head south was not acceptable. Starting at the base level, all '55-59 Chevrolet trucks came standard with a full assortment of gauges-full, that is, if you don't count a tachometer.
In the latter part of 1955, when Chevrolet changed from the model series of Advance Design to Task Force, they introduced what has come to be known as the "second series" of '55 trucks. The level of styling consciousness was raised with a V-shaped dashboard cluster that has withstood the test of time. In addition to a full-sweep speedometer, the classic '55-59 cluster incorporated oil pressure, water temperature, amperage, and a gas gauge.
Throughout the decades some of the inherent drawbacks that have come to light regarding the '55-59 V-cluster are related to gauge technology utilized in the mid-20th century. Starting with safety concerns, the worst problem is the amperage gauge that depends on a heavy-gauge wiring to work. Just Google "amp gauge fire" and you will learn that many a vehicle has burned to the ground when an amp gauge on the dashboard shorted out and started a fire. Next in line is the mechanical oil-pressure gauge on the V-cluster, which doesn't present any safety issues, but if the supply line breaks and goes undetected, the engine can run out of oil and blow up. On the bright side, if one is lucky the oil-pressure gauge will develop a slight leak close to gauge head and typically saturate the backside of the dashboard with oil. With the two biggies out of the way, we are left with the coolant temperature and gasoline gauges, which are identified with C and H, and E and F respectively, which is definitely better than a "game-over" idiot light.
To address all of the shortfalls normally associated with '55-59 V-clusters, there have been numerous designs introduced on the market. Most of which are made from billet aluminum and packed with an array of circular analog gauges, which, in design terms, one might say is a step backwards.
This was the state of affairs for '55-59 Chevrolet dash clusters up until February 2008, when the folks at Classic Instruments introduced one of the cleanest units to come along in a while: the Tach-Force. The Tach-Force pays homage to the Task-Force line of Chevrolet trucks and, true to its name, offers a tachometer in its assortment of gauges. Including a tachometer is just one of the really great features incorporated into the Tach-Force's design. Right off the top, the infamous amp gauge is replaced with a voltmeter, which instantly reflects whether or not the truck's charging system is keeping up with demands-and even indicates if the system is overcharging. In place of the mechanical oil-pressure gauge, the Tach-Force features an electronic unit that relies on a sending unit tapped directly into the main oil galley. The coolant temperature gauge on the Tach-Force is graduated from 140-280 degrees, and the gas gauge differs from the original with a "1/2" mark notated in the middle of the dial instead of an indicator dot. In keeping with the full-sweep design of the original speedometer face, the Tach-Force features a full-sweep scale that reads from 0 to 140 mph instead of 100 mph-and it's an electric instead of a mechanical unit that requires a cable for propulsion. Because the Tach-Force is fully electric and contains a microcomputer, it offers several programming options. For instance, the tachometer can be programmed for either six or eight cylinders, and the speedometer can be calibrated to work off of either a 5-volt ECM pulse, or a standard 12-volt source. On top of all the technical innovations over the stock Chevy cluster, the Tach-Force is available in four colors: light gray, cream, pure white, and a dark gray similar to the original color.
Classic Instruments' Tach-Force gauge cluster for '55-59 Chevrolet Task Force model trucks
Pictured above Classic Instruments' Tach-Force is the stock Chevrolet V-cluster as it appe
The Tach-Force comes fitted with an electric speedometer. For our truck equipped with a st
The threaded female end of the pulse signal generator contains a male stub formed exactly
The pulse generator was threaded completely down onto the speedo drive's retaining bracket
Then we plugged in the pulse generator's three-wire harness and routed it where it would n