How To Install Underride Traction Bars On Your Vintage Ford Mustang

Traction Master traction bars are old-school high-quality parts that work just as good now as they did 40-plus years ago. For those in southern California, Marlo's Frame stocks them. You can also order them from Tony D. Branda Mustang & Shelby Parts via phone or the company Web site. The Traction Master part number for '65-'66 Mustangs is TM1068. For '67-'73s, order PN TM1069.

All vintage Mustangs have a leaf-spring rear suspension, and while they're durable and easy to maintain, a major disadvantage is that the spring has a tendency to twist under hard acceleration. This type of load usually happens when accelerating hard on the street and more dramatically on the starting line of a dragstrip. The end result is often wheelhop, which can be violent if left unchecked. In a bad situation, wheelhop can break axles, snap springs, and possibly cause damage to the car's wheelhouse. Recall that only the leaf springs connect and locate the rear axle to the car.

For cars with high-horsepower engines, traction bars can be a good solution. Traction Master's underride traction bars-the same design used on '66 Shelby GT350s-are the perfect setup for the rear suspension on any vintage Mustang.

The bars are obviously a top-quality component, and the heavy construction of the bars themselves mean there's almost no way they'll bend. Furthermore, once in place, the bars also serve as trailing arms, solidly locating the axle in relation to the car. While some designs fasten at the forward end of the spring, the front mounting bracket of the Traction Master bars weld to the framerails under the car, providing new attachment points for the rear axle. So, the axle is no longer held in place solely by the leaf springs.

Finally, installation is easy, as the bars essentially bolt in place, save for a few minutes of welding that's required to attach the front mounting bracket. A good automotive welding/suspension shop near you (such as Marlo's Frame and Alignment, a local shop we use quite often) is the ideal place to help with such an installation.

The best access is afforded by raising the car and removing the rear wheels. Remove the U-bolt nuts and install the rear plate, securing it back in place with the original nuts. You might have to switch to longer U-bolts, which can be obtained from a local auto-parts store. As shown here, after the bar is removed from the plate so the plate can be installed separately, the plate is slipped into place on the U-bolts...	...then secured with the nuts. On this '66 Mustang, the setup has separate nuts for the shock-mount plate and the traction bars. You can do this, too, provided you get another set of nuts and the U-bolts are long enough.	With the traction-bar plate in place, tighten the nuts securely.
Although the car we are working with already has the front bracket welded in place, we can show you what it looks like installed here. When welding, the weight of the car must be on the tires for proper location of the front bracket. The bar should also be preliminarily installed to help locate the front bracket. A drive-on hoist works, or you can support the car with jackstands under the axle. Bounce the car up and down a few times to eliminate any preload. Then weld the bracket to the framerail. Be careful as the rail is thin and easy to burn through. To prevent rust, clean and paint the area after welding.	Once the front and rear brackets are installed (bolted in back, welded in front), it only takes a few minutes to install the bars. Begin by slipping the back of the traction bar into place on the plate as shown here.	With the rear in place and secured by a bolt, the front of the bar is attached to the front mounting bracket.
With the bar in place, securely tighten the nut on the front of the bar...	...followed by the one on the rear.	All done. The bars are a great addition to a reasonably quick street/strip type of Mustang that might have a set of slicks bolted to it for a little Saturday-night test-and-tune fun at the local dragstrip.