Don't worry about ordering bolts; Volvo didn't use anything unique - its all universally available stuff. It's all metric too, so super simple.
Getting the dimensions out of a parts catalogue helps to create a shopping list, but arguably the best person to decide what bolt is necessary is the guy on the ground i.e. you; because you can measure what you need.
These are the questions you need to ask, building you a bolt spec:
What diameter thread?
Measure and decide... will be M8, M10, M12 etc. Numbers are millimetres tip to tip of the threads to create a thread diameter. They normally come in just under, so an M10 is about 9.8mm
What length?
A length of a bolt is not the total length - you never measure the head. Again, metric in mm to 5mm derivatives.
Threaded or part threaded
Technically this is the difference between a set screw and bolt. The whole bolt threaded, or a part-threaded shank? If part-threaded, think about your protrusion and how far the nut will travel. You don't want a nut to bottom out on the non-threaded shank.
Pitch
The 'courseness' of threads in .25 steps... typically 1.25, 1.5, 1.75 etc.
Strength
8.8 is 'normal'.
10.9 is for stronger suspension stuff.
12.9 is for super high torque stuff.
Buy bolts from a reputable source and make sure this strength reference is stamped on the top.
Finish
Zinc, stainless, dark metal... your choice really. Stainless tends to be more brittle for suspension work. Yellow passivate gives a nice OE look.
My last bolt purchase for my trailing arms were Zinc GEOMET coated... they are gorgeous... but I guess it's only me that gets excited by bolts
So consider your application, measure and you come up with something like
M10x45x1.25 part threaded 10.9 Zinc Plated
With that, head to your chosen supplier. I use either Kays Fasteners or Bolt World. Both have online shops.
I like flange bolts and flange nuts because they have a nice seat flange. They torque down better in my opinion.
If a bolt passes through a metal sleeved bush, copper slip the bolt shank (not threads!) as it will be easier to remove in a few years.
Also, get yourself a metric thread file....
These are handy because not only do they tidy damaged/corroded bolt threads, but it's also an excellent thread pitch gauge for quickly checking what pitch bolts are.
A common mistake I see all the time is a lock nut used on a bolt that is not quite long enough - so the nyloc part of the nut doesn't actually have full thread interaction. Make sure the bolt fully protrudes through a nyloc!
Just like bolts, I would argue brake pipe is another safety critical item and I am just so sceptical of eBay. My last reel of 3/16ths was from Euro Car Parts. "SAVILLE" by name, EN12449 approved, seamless, burst tested and internal cleanliness verified.
Don't forget a dob of stud lock on caliper carrier bolts.
Oh, and I can't recommend a Gunsons Eezibleed enough; also less than £20 from ECP. You will never get the other half to pump a pedal again
Good luck!
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