If there’s one quality we can confidently say almost all diesel trucks have in common—especially today’s pickups—it’s their height. From the factory and through modifications made by aftermarket customizers, the lion’s share of Ford, Chevrolet, GMC, and Ram rigs on the road today stand pretty tall.
A truck’s elevation typically comes by way of its powertrain configuration (four-wheel drive), big wheels and tall tires, and/or suspension setup. And, depending on the way all these elements are integrated, using an extension ladder may sometimes seem like the only viable method for entering or exiting the vehicle. Of course, and thankfully in most cases, simple access or egress isn’t that extreme. And, for instances when a truck might be a little too high for safe navigation into and out of the cockpit, steps of various sorts can be added in the better part of an afternoon.
The first running boards were on horse-drawn carriages and trains. All cars and trucks had running boards until about the 1930s, since the body usually sat within the framerails rather than surrounding them. We’re pretty sure there are a lot of truck owners and passengers who are thankful for their invention—and their evolution from plain, flat wood, metal, or fiberglass panels that basically attach to the frame just below a truck’s doorsill to tubular “rails” that are a bit more stylish than running boards.
| Diesel Power Tech Editor John Lehenbauer secures a billet linkage arm for AMP Research’s PowerStep, which we’re installing on a ’16 Chevrolet Colorado…diesel powered, of course.
Although we’re not introducing new breakthroughs in overall side-step purpose with this project—installing PowerStep Retractable Running Boards from AMP Research (PN 76153-01A)—this particular system was selected for our 2.8L Duramax-powered ’16 Chevrolet Colorado LT crew cab because of its plug-and-play simplicity (thanks, in part, to AMP’s new Pass-Through Harness [PN 76404-01A]) and the fact that it’s seen only when in use or manually activated via an all-new Override Switch (PN 79105-01A). Despite this project vehicle’s suspension being 100 percent stock, its four-wheel-drive stance is tall enough to make maneuvering into and out of the cabin somewhat difficult, especially for Crystal Jones, the owner of this particular Colorado and the vertically challenged wife of Diesel Power Editor KJ Jones.
Two 72-inch aluminum steps and their associated brackets, motors, electrical wiring, LED lights, and all necessary hardware are all included with the system. It can be installed as a do-it-with-a-friend, in-the-driveway project, as demonstrated by Tech Editor John Lehenbauer, who expertly bolted in and wired our setup in an 8-hour workday.
| Amp 2016 Chevrolet Colorado
| With our test truck sitting at its standard, unmodified ride height, the ground-to-entry distance measures 21 inches. For some people, this is not very high. However, other folks, like this Colorado’s 5-foot, 3-inch owner/driver, climbing into the cockpit is a daunting task that must be done with calculated precision.
| The AMP Research PowerStep kit for ’15-to-’16 Chevrolet Colorado and GMC Canyons (PN 76153-01A) is all-inclusive, highlighted of course by two retractable, 72-inch aluminum boards. Only a small assortment of simple handtools (a drill and 1/8-, 9/32-, and 21/64-inch bits see the most action) is all that’s required for installing the system.
| Being exact with all the measurements—and there are many—is very important to ensure the PowerStep are installed in their correct positions and operate smoothly. The pinch welds running along both sides of the truck’s undercarriage serve as index and anchor points for brackets and LED lights.
| AMP Research provides a “rivet nut” (we know them as nutserts) that’s used for securing the steps’ front linkage brackets. On both sides, natural holes in the front body crossmember must be enlarged to 17/32 inch. The rivet nuts are then installed with a special tool that is included.
| As the linkage placement stems from positions on the truck’s rocker panels and crossmembers beneath it, we can’t stress the importance of making correct measurements and drilling accurate holes enough (a template is provided to index the 21/64-inch holes that are bored in the rocker panel). Failure to install linkages in their proper location will compromise the PowerStep’s automatic function and ability to support its advertised maximum weight (450 pounds).
| Amp Bracket
| Installing the PowerStep linkages is basically a repetitive, symmetrical task. When one side is finished, the same operation is performed on the other side (same measurements and such). Once all the linkages are in place, John leaves them slightly loose to allow for any adjustments that are necessary before final tightening.
| Amp Brackets
| While the system’s wiring harness seems endless—and possibly too big for the Colorado—when it’s initially unbundled, the harness is actually the perfect length, with connectors for the LED lights and PowerStep electric motors falling exactly where they’re supposed to be along the truck’s rocker panels.
| After removing the system’s 30-amp fuse and connecting 12-volt and ground wires to the battery, John guides the wiring harness down toward the undercarriage on the driver side. Wires for the passenger-side PowerStep run across the engine at the firewall and into a similar pocket in the back corner of the engine compartment.
| Amp Interior Removal
| John removes the driver-side doorsill and kick panels and brings the PowerStep system’s control wires into the cabin
| Amp Harness
| Here is a look at the AMP Research pass-through harness (PN 76404-01A) that makes connecting the PowerStep controller to the truck’s OBD II port a piece of cake. The steps are operated by the Colorado’s door circuit (they extend when a door is opened and retract when a door is closed). Older units required determining which wire controlled a vehicle’s door-related accessories (dome light, door chime, and so on) and tapping into that wire to control the steps. AMP Research developed a control module that communicates directly with the vehicle’s ECM to determine door function and operate the steps accordingly. We like the pass-through harness because it allows us to establish a link between the truck and step system and retain a functioning OBDII port inside the truck (in its original location).
| Even the LED lights are mounted in a specific location along the rocker panels. Measurements are taken from the rear edge of the front and rear linkages.
| After thoroughly cleaning the mounting surface (below the rocker panel), the lights are affixed to the truck with 3M two-sided adhesive.
| The LED lights are tied to their respective ends on the PowerStep’s main wiring harness, using butt connectors included in the set.
| When working on projects like this, using a vehicle’s “natural” holes and anchor points is always a good practice. We used the Colorado’s bed-bushing mount as a support for the PowerStep’s wiring harness.
| Installing motors for each step extrusion is straightforward. Each motor is secured to the front linkages with two bolts that are included.
| Once all the major hardware installation is completed, the 30-amp fuse is plugged back into its socket.
| Wiring for the AMP Research PowerStep’s control module is plug-and-play, as the main harness and a harness for the override switch snap directly into their respective outlets. We simply tucked the module next to the battery case.
| In the engine compartment, only the system’s control module is visible.
| We’re also installing AMP Research’s override switch (PN 79105-01A), which takes the PowerStep out of automatic-operating mode and allows users to manually deploy or retract the steps and leave them locked in either position for 30 minutes. Instead of blasting a 13/16-inch hole in the dash, John is mounting the switch in an easy-to-reach location at the base of the driver seat.
| Amp Switch Installing
| Toggle Up: Running boards retract and remain in stowed position, even when a door is opened.
Neutral: Running boards operate automatically when doors are opened and closed.
Toggle Down: Running boards deploy and remain in deployed position, even when the doors are closed.
| Amp Step Down
| AMP Research PowerStep…deployed.
| Amp Step Up
| AMP Research PowerStep…retracted. Notice how the step extrusion covers the entire rocker panel, blocking the pinch weld and giving the Colorado a clean profile.
| With the steps down, distance between the ground and the top of the running boards is only 9.5 inches, dramatically shorter than the 21-inch climb directly into the cab.
| Amp Step Night