Thread pitch for skidplate bolts?

[Palmer]

Hey all,


I have a skid plate waiting to go on, and I need the hardware, as it did not come with any.

2002 WRX wagon.

What size do I need? I tried about 5 bolts I had in my garage, and the thread was too coarse. Is it fine thread?

Thanks!

[williaty]

M8x1.25

Lengths necessary vary.

[Palmer]

I tried 1.25, and it did not fit.

I think I may need to run a tap through or something. Stuff looks a little corroded.

[williaty]

They're 1.25 thread pitch.

If it didn't fit, either your bolt wasn't 1.25, the threads on one or the other were damaged, or the hole is full of rust.

[Palmer]

I'll get a tap set, I need an excuse to buy one.

[williaty]

Do yourself a favor and order the taps from McMaster.com. Because Subaru uses the JIS spec, you don't need all the stuff that comes in any tap set. You need:
M6x1.00
M8x1.25
M10x1.25
M12x1.25
M14x1.5

And that'll do everything on the car except the holes in the rear diff cover plate for the mounting studs (they're M12x1.75 and the only thing on the car that coarse). You need all of those sizes in a plug tap at minimum. Getting those sizes in a bottoming tap as well is also a good idea. Whatever you do, absolutely get them in the Titanium-Nitride coating (TiN coating). I was SHOCKED how much better they cut with that coating.

Additionally, it's worth having a rethreading die for each of those sizes. With the taps and the rethreading dies, you can save a lot of bad situations.

[Palmer]

Right on. Thanks for the info!