SLK Boing!

[Deleted member 6183]

Not sure which section this sits so will try here first.

My Mrs has been complaining about a boing in the boot of the SLK, now she often does this kind of thing - sometimes it just 'farty' or 'holding back' and sometimes 'feels like it's going to conk out' so I was a bit sceptical.

I took it for a run recently and, sure enough, it does occasionally 'boing' from the boot area. Have emptied the boot out of all her stuff and it still does it.

It seems to effect her more than me and I can't replicate the conditions that create the noise consistently, if I had to pin it down I'd say under hard acceleration but not always.

It happens less frequently with the roof down.

Any suggestions?

 

[Conquistador]

Something loose in the spare wheel well by any chance?

 

[Howard]

Boot closing spring moving about ?

 

[SLKNick]

Mine made that sort of noise whenever the rear of the car went light going over humps etc.

Turned out to be a broken rear spring, half a coil snapped off at the bottom. It was difficult to spot on visual inspection as the spring pans are so deep but is a fairly common issue. One had already been replaced by a previous owner.

New springs from dealership were only £66 per side and took me less than 2 hours to change both.

 

[Deleted member 6183]

Mine made that sort of noise whenever the rear of the car went light going over humps etc.

Turned out to be a broken rear spring, half a coil snapped off at the bottom. It was difficult to spot on visual inspection as the spring pans are so deep but is a fairly common issue. One had already been replaced by a previous owner.

New springs from dealership were only £66 per side and took me less than 2 hours to change both.

This sounds likely, the boot closing spring was my first thought but I see no spring only hinges and motors.

I'll pop it into my mechanic for a squint sometime soon.

Were there any other symptoms for the broken spring?

 

[SLKNick]

No boot closing spring on our SLK's, just relies on gravity and the gas struts.

In theory, if you park the car on level ground and measure the vertical distance from the wheel centre to the wheel arch, the measurement should be the same on both sides. If a spring has broken you should be able to see a difference in the measurement. However, this is not always reliable because springs sometimes get tired, worn bushes can also affect the measurement.

In my case a previous owner had replaced the other spring with one which was slightly shorter, so when mine went the height was the same both sides. There were no other obvious signs when my spring broke, only the boing sound.