What size is the head of the bolt?

 

Bolt head and nut are both 14mm.

 

If that is the bolt you want, just measure it.

I went looking for the information you requested but couldn't find a reputable source. Maybe 8mm, maybe 10mm.

Also, you could get the bolt and washer from Subaru and deal with the nut separately in the aftermarket.

 

I found some AI info saying they were 10mm, then something else saying 12mm. Also, AI seemed to think the front and rear bolts are different lengths, though I'm not sure why that would be the case. Thanks for taking the time to search for accurate info, donkpow. I appreciate the effort!

 

Be sure you get high strength bolts and nuts. For example, an M10-1.5 bolt (10 mm diameter, 1.5 mm per thread) has tensile strengths ranging from 23200 Fm,min for the 4.6 class to 70800 12.9 class. Buy the highest class, the strongest, you can get.

 

I've had luck calling dealer auto parts departments. go right to the source. if they aren't crazy busy, those ppl like to help

 

Thanks for the useful tips, KennethL and Rumrunner! I messaged one of the online Subaru parts sellers, and if I don't hear back, I'll try the dealer route.