Thursday, July 14, 2016

Torsion Bars

Had to learn the hard way that torsion bars are NOT interchangeable in which side they go onto the vehicle.

My neighbor's '94 Chevy Suburban needed a new transmission. In removing the transmission, the left torsion bar was in the way of the transfer case, and the cross bracket that holds both bars was in the way of the transmission...so they all needed to be removed. When putting everything back together, and getting to reinstalling the torsion bars, I started with the driver's side. The key that fits over the end of the bar, and between the cross bracket, would not tighten into it's proper place. The torque needed to get it into place would've been enormous. It wasn't that tight coming off...something was not quite right.

Torsion bars are solid, steel bars, usually with large hex heads at each end. They take the place of the suspension springs found in many early model vehicles. The lack of these springs allows for more room in the engine compartment. Each bar anchors to it's respective control arm, and to each side of a cross bracket under the middle of the vehicle. An adjustable key is attached to the end of each bar, causing a twisting action on the bars. This twisting action gives the vehicle it's lift, while providing cushion when driving...just as springs do.

After hours of research, I found out that torsion bars are "pre-sprung" in one direction only, meaning that they had to go on the correct side of the vehicle. It DOES matter which bar you install on what side of the vehicle! I was trying to get the wrong torsion bar to work...and believe me, it doesn't.

Each bar has information stamped on the ends of the hex head. Usually, there are one to three pieces of information. One piece of information may be an arrow showing the direction of the bar's torsion. Another may be an "L" or "R", indicating what side of the vehicle the bar is to be installed. Usually, all bars have a number stamped on them. The lower number indicates installation on the left side of the vehicle, while the larger number indicates the right side.

Hopefully, this will help someone install his or her torsion bars right the first time, unlike myself.