is it safe to drive a vehicle with failing trailing arm bushing suspension?
In most cases, bushings won't be so bad since the trailing arms are going to come off the vehicle. But since you asked about safety and suggested they are failing, I have to wonder what condition they are in. I have not yet seen a car that had trailing arms that were going to come off the car. Also, it seems it would not wobble so much that the car could not predictably drive in a consistent direction. Most of the time bushings will cause clunks, tire wear or pulling to one direction. In these cases, there isn't a safety issue, other than your car pulling to one direction when you take your hands off the steering wheel, which I don't suggest you do anyhow.
In the vast majority of cases, bad trailing arm bushings are not a safety issue. If they are a safety issue, you would notice your car moving around very erratically while driving. In other words, you would not be able to control your car. If this is the case, then yes, it is a safety issue.
In either case, if you are not absolutely sure, I recommend the following inspection to help you out. A certified technician from YourMechanic can come to your home or office and replace your trailing arm bushing.
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