Car under tray spring washer replacement

Noticed the under tray on my car was hanging down on one end, looks like one of the spring washer attachments has rusted and failed. There is a threaded stud on the car body that looks okay. I’ve ordered a pack of replacements but was wondering how they attach – do they just push on and held in place with the teeth, or do I have to wind it on?

From zooming in they look like they just push on. Make sure you push on the clip and not the undertray itself

Is the stud suitable for a nut?

A stainless washer and nut would be a better rust-free solution; I expect it’s about ease of assembly and time on the factory line

Yeah that’s what I thought but can’t get a definitive answer anywhere, only that to remove them from the stud you need to wind them off. It’s a bit tricky to reach this area tbh on the flat. How bad an idea is it to reverse the car onto some bricks to raise it a couple of inches whilst I replace it…

@timba – possibly it would yep, maybe worth looking into as well

How bad an idea is it to reverse the car onto some bricks to raise it a couple of inches whilst I replace it…

Badder than a bad idea. Stability of the jenga pile, crumbly nature of bricks, etc.

Tap the old one out with a hammer and screwdriver/drift.  The fact it is rusted should reduce/remove the spring effect.

Tap the new one into place and the spring effect should clip it into place.

Bricks is a bad idea but a concrete block (breeze block but more solid) is a slightly less bad idea if you don’t have jacks/axle stands

One side up on the kerb if you have a quiet street that you can lay under without getting run over.

Star washers are a quick way to fit something relatively light (like an undertray) to a threaded or shouldered stud on a production line. Likely to be a standard threaded stud behind so a big repair washer and nyloc nut would hold it safely without having to remove the existing one.