Rear suspension–trailing arm replacement

Here is a major suspension component that is susceptible to corrosion and rust of the worst kind. In this article I will show you a worst case scenario of why these trailing arms have a problem and how to replace them.

This repair was on a 1995 Oldsmobile Cutlass Supreme. Use this repair as an opportunity to also see that looks can be deceiving especially when purchasing a used car.

This is a one owner vehicle with 85,000 miles and very clean inside and out. The customer concern is a vibration and shimmy from the rear of the vehicle at highway speeds.

Upon removing the wheel you can immediately see where the problem is.

The left rear trailing arm is completely broken in two pieces.

What could happen?

This is an accident waiting to happen. On dry pavement it would have a wandering feel from the rear and severe tire wear or tire damage if not caught in time. With rain or snow conditions this could be more severe with over steering of the car and you could lose control possibly causing an accident.

Parts

These parts are only available from your local General Motors dealership.

The aftermarket parts suppliers don’t show a listing on this part.

Jack up, support the vehicle, and remove the wheel.

Note: Refer to the “Helpful knowledge section” for supporting article to help you with this job. You will need to know about removing and installing a wheel and how to use a jack and jack stands.

Check to make sure the arms are the correct size and length before removing from the car.

There are only two bolts and two clips holding the arms onto the vehicle.

Remove the rear bolt using a breaker bar with a 24mm socket and wrench to hold.

Remove the 2 spring clips that attach the ABS wheel speed sensor harness from the arm.

The front mounting bolt is 19mm

Break the bolt loose and remove it from the front arm.

Remove the arm from the vehicle

Once the arm is removed, you can really see how corroded they get from exposure to road salt.

This is what winter weather does to this type of car over a period of 13 years in Indiana.

Here’s a closer look at the broken arm

Start by installing the front part of the arm into the body mount

Then install and draw up snug, but do not tighten the front nut and bolt until both ends are installed. This will allow for easy movement of the arm when installing the other bolt.

Swing the arm into place and line up the bolt hole

Install the rear nut and bolt. Now you can tighten both ends.

The arm is marked with an X where the harness clips attach

This is what a properly routed harness looks like.

If the clips are broken or rusted through, obtain new clips from the dealer or tie wrap out of the way to prevent damage to the harness. If damage occurs to this harness the ABS warning light will come on and the left rear speed sensor will not register.

Estimate

When replacing trailing arms in such bad condition like these were, I would recommend to replace both arms, even if only one is broke because the other arm is aged the same and is not far from braking as well. To replace the trailing arms it took approximately 30 to 45 minutes per side. Some of the rust may fight you during replacement. My recommendation is to use PB blaster penetrating oil to help with freeing up the rusty nuts and bolts.

Comparison Pricing

Do it yourself repair
2 arms approx. $150

Repaired at a shop
$440 plus tax
2 arms approx. $200 or more with a labor charge of 1 1/2hours per side @ $80 per hour for shop labor.