Jim Smart
August 1, 2001

Driveshafts do a big job in our Fords, Mercs, and Lincolns. They take a powertrain's rotary motion and carry it to the differential and drive axles. This is not an easy task. Not only must a driveshaft transmit rotary power without failure, it must articulate with the up-and-down movement of the rear axle as we cruise over highs and lows in the road. Highs and lows range from smooth transitions to really rough ones.

We visited Inland Empire Driveline (IED) for a closer look at driveshafts, universals joints, and yokes. What we learned from IED applies to every one of our readers out there, so listen up. Even if you're building a restomod with stock driveline components, you need IED to get you on the right track with Spicer universal joints and yokes. This ensures the kind of driveline integrity you need and want for drivers and show cars alike. And when it comes to the driveline, there are no unimportant parts.

If your Ford has a two-piece steel-over-rubber driveshaft, which was popular during the '60s, with automatic applications to absorb vibration, we suggest having a new shaft made. These vibration-absorbing shafts have deteriorated over time to where they're prone to the very thing they were designed to prevent: vibration. IED can make for you a new precision-balanced, one-piece shaft for vibration-free operation.

We're having an aluminum driveshaft made for a '67 Mustang with C4 Cruise-O-Matic and a Gear Vendors (GV) Overdrive unit. This calls for specialized driveshaft fabrication by the experts at IED. Because the Gear Vendors Overdrive unit is 14 inches long, this makes our C4 14 inches longer than it was in stock form. We've measured our application and have concluded our shaft needs to be 37 inches from center to center (universal joints). Pinion angle at the differential will have to change to accommodate the shorter driveshaft. We're going to show you how to do this later in the article.

How A Driveshaft Is Made
IED has our driveshaft specifications nailed down. We need a shaft that's 37 inches center to center. Tom Aragon of IED is going to custom-make an aluminum driveshaft for us designed for a '67 Mustang with GV Overdrive. We'll then show you how to install and set up the shaft.

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