Tachometer Installation

This how-to article will cover the installation of a tach on 1995 and later Ford Ranger vehicles. Although this particular article will be vehicle specific, similar principles will apply to all vehicles utilizing an electric tachometer.

Q: Why should one consider installing a "tach"?

A: The tachometer can be a very useful diagnostic tool, especially on vehicles that did not come factory equiped with one. In order to properly calculate the necessary and/or desired gear ratio to re-gear the rear differential after installing larger diameter tires, we need to know the exact engine RPM values at given speeds. The tachometer is one of many ways to monitor a vehicle, and can yield great insight while performance tuning your desert ride.

Required/Recommended Tools :

Difficulty Level : Intermediate

---

Step 1: Select and Purchase a Tach

There are many things to consider while shopping for a tach. Brand name quality and reputation, accuracy, and overall style should be the determining factors. Autometer makes some of the best vehicle performance instruments, and many racing teams have chosen to run them.This is why I decided to run one of their tachs in my vehicle. Autometer makes a series of liquid-filled guages, which are the ultimate off-road instruments. These liquid filled gauges resist the vibrations that our vehicles are subjected to, however, they come at a far higher cost. Liquid filled gauges can cost 3-4 times as much as a standard guage. I purchased my tach at a local auto parts store, and spent about $110.00 (regular tach, non liquid filled, and no fancy shift light). Better deals are sure to be had, especially online, so shop around.

---

Step 2: Decide on the Placement of the Tach

Placement of the tach is up to you. It is recommended that the placement should be in a location that does not obstruct the vision of the driver, but also in a spot that the driver can easily see. In my truck, this was in the furthermost corner of the dash on the driver's side.

---

Step 3: Attach the Mounting Bracket to the Dash

In this case, mounting the bracket involves nothing more than screwing in two self-tapping screws through the holes in the mounting bracket.

---

Step 4: Attach and Secure Gauge to Mount

This should be obvious.

---

Step 5: Wire the Tach

Before you can begin wiring the tach, you will need to locate a good ground to connect to. The supplied wire will not reach to the battery, nor will it reach far enough to mount to a ground in the engine bay. It will have to be grounded inside the cab, and under the dash. The black unpainted bolts are usually grounds.You will also need to determine which wires you can tie into that will give your tach light power when only the parking and headlamps are on, and normal power anytime the car is running.All of these wires can be determined by using a test light, and individually probing the wires. This is the part of the installation that will take the longest.Because the wiring will vary from model year, and there are many permutations that can allow for the proper wiring, you will need to use the test light method.Attach the wires to the proper locations as shown in the wiring diagram that came with your tach. Pick up and install the in-line fuse that the manufacturer of your tach recommends. This fuse is important!You will need to splice the green wire into the Computer, which will be located on the passenger side firewall. The wire/pin to splice into is pin#48, which is a brown or tan wire with a yellow stripe. This information applies to all Ford Rangers, 1995 to present.