If you're tired of mentally calculating your actual speed, this ingenious little device will make you really happy.
The GoWesty SCD (speedometer correction device) for the 4WD Syncro installs in just a few minutes—simply unscrew the speedometer cable from your front differential, install this box, and reattach your speedometer cable to the box and—voila!—the speedometer and odometer are accurate.
In order to determine exactly which SCD box you need, please do the following:
• You'll need an accurate GPS device to determine your actual speed.
• Get your vehicle out on the highway (or somewhere where you can safely travel at speed).
• At exactly 50 mph on the GPS unit, note the speed indicated on your speedometer. We recommend having a friend present to read the GPS unit.
• Use the drop-down menu above to order the correct SCD unit.
• Receive the part and screw it in.
• That's it! Now you're cooking with gas.
We have experimented with all sorts of "in-line" corrective devices—and the bottom line is that they're just not accurate. This unit is the real-deal, it's been tested over and over, and it works.
Note: We always recommend replacing your speedometer cable (see related items below), especially if your vehicle has the original two-piece cable with the black EGR box. A sticky speedometer cable can cause your speed reading to be inaccurate.
Note: Your "speedometer" is actually an assembly of two gauges: a speedometer and an odometer. It is possible for there to be something wrong with your speedometer assembly, whereby the speed reading is off by a different percentage than the odometer reading, and correcting just the speed reading with our SCD-4WD will not make the odometer read accurately. In addition to checking the speed reading with a GPS, you should also check the odometer distance reading for accuracy. If the speed reading is off by a different percentage than the odometer: Replace the assembly with a rebuilt unit—see related items below.