Strut piston lateral wear/movement?

[lukeyman]

Hi.

Is it possible for a strut to wear so that the piston can move sideways? We've got a constant knocking noise and a front wheel that rocks in and out at 12 o'clock while it's on the ground... but as soon as it's jacked up it won't rock. And then the rocking sometimes doesn't come back until the car has been driven for a bit.

All the usual moving parts seem fine and I've already swapped the top mount... obviously not thinking to give the shock a once over at the time!

Cheers.

[GreenV8S]

Anything's possible, but that would be pretty easy to detect. A wheel bearing or balljoint failure seems more likely though.

[PhillipM]

Yes, common failure issue especially if the strut leaked it's oil out first.

[stevieturbo]

Easiest way is to just rock it and see where is moving.

If it's that much, it should be extremely easy to see.

[E-bmw]

GreenV8S said:

Anything's possible, but that would be pretty easy to detect. A wheel bearing or balljoint failure seems more likely though.

^^^^ Wot 'e said.

Much more likely a wheel bearing/upper ball joint from your description.

[lukeyman]

Thanks for the replies.

It doesn't have any upper ball joints...

Wouldn't a loose wheel bearing be felt at any hand position and regardless if it was in the air or not?

[GreenV8S]

lukeyman said:

It doesn't have any upper ball joints...

I didn't say upper.

lukeyman said:

Wouldn't a loose wheel bearing be felt at any hand position and regardless if it was in the air or not?

No. A damaged race will only be perceptable when the point of damage is loaded.

[lukeyman]

GreenV8S said:

lukeyman said:

It doesn't have any upper ball joints...

I didn't say upper.

lukeyman said:

Wouldn't a loose wheel bearing be felt at any hand position and regardless if it was in the air or not?

No. A damaged race will only be perceptable when the point of damage is loaded.

I didn’t say you did…

Thanks for the extra info on the bearing. Shock first.

[lukeyman]

Just to follow up; it was the piston rattling in the strut. There didn't seem to be any evidence of a leak but there was noticeably less damping compared to the new one.

Cheers.