Broken Rear Radius Rods?

[LightlyToasted]

OK, yes, those are (were?) the radius arms. I'm not sure of their specific purpose, but learned long ago that once one part of a suspension system is weak or broken, the additional stress causes other parts in the system to get weak or fail.


I'm not sure if missing radius arms would cause clunking, but a worn ball joint or bushing or end link or rear shock mount can. Pry or squeeze (with large channel lock pliers) all of the ones that you can see. If the noise is easily reproduced by bouncing the vehicle around in your garage, it helps a lot to have it up on ramps and have a helper bounce it while you look underneath at what is moving excessively.



I'll be going through a similar process to locate the source of rear end sway on mine. I can actually push on the rear quarter panel and the vehicle will oscillate side to side.

[DoubleA98391]

I will have to try this. Everything seems tight with the tires in the air but that isn't how it drives down the road. I'm just curious about how they broke in the first place. They are up out of the way of debris from the road. But maybe since they're cast aluminum a big pothole could do the job?

[LightlyToasted]

Originally Posted by DoubleA98391

I will have to try this. Everything seems tight with the tires in the air but that isn't how it drives down the road. I'm just curious about how they broke in the first place. They are up out of the way of debris from the road. But maybe since they're cast aluminum a big pothole could do the job?

Maybe, but that wouldn't be my guess. I'd suspect metal fatigue, possibly from something else being worn and causing excess movement and additional stress on that part. I have some experience with metal fatigue issues in the rear end of E36 and E46 chassis cars. It's interesting though that yours are broken on both ends; I'd expect metal fatigue would break one side and the other side would dangle. I'd be interested in hearing from others who've had this problem. I'll check mine tonight. I'm actually hopeful that this is it, as it looks straightforward to replace.

[LightlyToasted]

Mine are OK. Will check ball joints and bushings this weekend.