Torsion Tips

Torsion Bar Front Suspension Rebuild Tips and Tricks: Part One

Chrysler introduced its revolutionary Torsion-Aire front suspension system in 1957 and a new standard of handling capability was achieved. At the time, virtually every U.S. built passenger car relied on coil springs up front. Essentially made up of wire that’s wound into a 12 to 24 inch tall, 6 to 10 inch round cylinder (compressed), coil springs must be mounted vertically above the upper or lower control arm in order to react against the vehicle body – and support the car. Packaging these vertical springs eats up space and forces the need (in some cases) for bulky spring towers inside the engine bay. Just ask any Ford Mustang owner how these spring towers interfere with spark plug changes, header work and big block swaps.

Another ding against coil springs is their inability to offer a firm ride when pushed during hard cornering. Sure, adding a front sway bar and stiff shocks can crutch this tendency but Detroit has always erred on the side of comfort when it comes to factory suspension settings. As such, most coil spring cars are known for their soft “boulevard ride”, but not for extreme cornering capability.

Getting back to Chrysler’s plan, the engineers replaced the twin coils with simple chrome vanadium rods about 3 feet long – the torsion bars. As the name implies, they’re mounted horizontally under the front floor and frame with the rearmost ends anchored so they cannot rotate. The leading ends of the rods fit into similar hex-shaped receptacles in the lower control arms. When loaded with the weight of the car, the rods see a twisting or torsional load. By resisting this load, the simple steel “rods” (they’re actually highly engineered in every regard) serve as springs.

Torsion-Aire proved to be highly effective and with changes to suit various vehicle platforms, every domestic market Chrysler Corp. passenger car made from 1957 through 1975 (excepting captive imports like the Sunbeam Tiger, Plymouth Cricket and Dodge Colt) was equipped with a version of the basic torsion bar front suspension. But was Chrysler alone in its appreciation of torsion bars? No way. GM adopted a similar setup under GMC pickup trucks in the early Sixties and also used ‘em under the front wheel drive Olds Toronado (1966) / Caddy Eldorado (1967) luxury cars for over a decade. European makers have also embraced the compact packaging of torsion bars since the dawn of the motorcar and continue to do so today.

Let’s dig in and show what it takes to rebuild a worn out torsion bar front suspension on a 1966 Barracuda.

How do you know when it’s time for a front end rebuild? In the case of my ’66 Barracuda, the need was obvious any time I applied the brakes and the left front tire jammed rearward an inch. Naturally this was accompanied by a nasty steering wheel pull and change of direction into oncoming traffic. At first I hoped the cause was worn strut rod bushings. Highlighted here, all Mopar A, B, C and E bodies rely on solid steel strut rods that run between the K-frame and lower control arm. They resist braking force and help keep the front wheels located. Yes, there is a small amount of deflection designed into the system – but not an inch.