Is this off my car?

[ScarbSaab]

Might be a daft question as I think it looks like more than a night's corrosion, but I'm hoping that if it is likely to be off my car ('04 9-5 Aero auto), you will able to point me at where to check.

Coming back on Tuesday night, I was ready to reverse into a gap. As I released the brake and started moving back there was a loud 'clong'. It was dark, but nothing was visually amiss. Yesterday, I had a look under the car and it was sat level, and there wasn't anything obviously loose. However, I found this in the road right where I had been reversing.

The measurements are: overall length = 21.5mm, threaded length = 16mm, thread diameter = 4.9mm, allen key size = 4mm

[sgould]

That doesn't look as if it's been on anything in ages.

And the loud bang from the handbrake is normal.  It does free off for a bit once it's banged, but try pulling on the handbrake at 10 mph.  It will make a loud bang if it's the first time it's been used like that for a day.  Something to do with the way the handbrake shoes are fixed.

[ScarbSaab]

Thanks sgould. I thought that was likely to be the case, but I don't like coincidences.

I should have been more specific - I released the foot brake. I had covered about 200 miles that day in four trips, reversing at the end of each run. This was last thing at night, at the end of a 40 mile drive without using the hand brake. I suppose it could be the hand brake, but I've never known it do that before on getting home.

[sgould]

Most times the handbrake is applied after you have stopped.  If you put on the handbrake even when moving very slowly, it will bang.

[harryO]

It looks like one of the bolts that secure the cam cover (rockerbox) but they are a bit longer. As you say, it has been off the car for a very long time.

Might have been been dropped into the bottom of one of the plastic trays under the car a good many years ago during a service, replaced and only just found it's way out.

[phoenix]

Looks more like it's off a pushbike. There's very few (if any?) allen head bolts on Saabs.

[ScarbSaab]

Sorry guys. Didn't mean to have you scouring the car for missing bolts! It was just that I found it where the car had been when I heard the noise, but as sgould pointed out, it's more than one night's rust. I'm satisfied that there's nothing about to drop off my car.

[TomPaine]

I'm satisfied that there's nothing about to drop off my car.

Cue a fresh ScarbSaab thread in the next few days entitled "Where to source a new exhaust?"...