I hope to be replacing the shock absorbers on my 2005 Mazda 3 this weekend. I have purchased the shocks themselves (Monroe P/N 5607), as well as new mounts. The only thing left to get is new bolts....
From watching this video, I can tell that it is a 17mm bolt. The question is can I just go out and buy any 17mm bolt that is the same length as the current one, or is there some kind of material requirement?
The question is can I just go out and buy any 17mm bolt that is the same length as the current one,
No.
or is there some kind of material requirement?
Yes.
Think about the jobs that those bolts are doing: they support the steady state mass of the vehicle and the transient spring loads of the transmission. That means that those bolts need to be strong enough to handle steady loads as well as sudden impulses.
You aren't going to be able to just throw any old bolt in that slot and expect it to hold up.
A lot of the bolts under transient loads on the car are grade 8. Check the bolt that you're removing against this handy reference sheet. You want to make sure that any replacement bolt is at least as strong as the one that's coming out.
Not sure why you want to replace the bolts you should be able to reuse the original bolts. If you do decide you want new replacement bolts make sure to get the correct size. Bolt size is determined by the size of the bolt (not the head) and the thread. You will need to get the correct thread pitch, diameter, length, and strength. You could call your local dealer and they may have the bolt or be able to tell you the size if it's a standard bolt.
