Shock linkage bolts.

I am about to change the rear damper/shock on my K9, I "may" have to space the link arm/dogbone on one side to give clearance for the nut on the bottom damper bolt (not the normal shock change). Therfore may have to make a pair of longer bolts up to take a 2/3 mil spacer?
Has anyone any idea what the GRADE of the material the standard bolts are, they are marked on the head with either a d or p I have had a reasonable search but cannot find a reference to the grade, I am guessing they are a high tensile grade BUT as YC pointed out it is probably the shear strength that is more important, ALL advice appreciated.

Because the shock being used is not the norm I will document and post the progress In case of interest to others.

JOHN

[yorkie_chris]

why do you need to space it out? One shock or another all you had to do was fit the bottom clevis on backwards.

Also grinding .6mm off bolt head won't hurt.

Interested to note what shock you are using.

Hi Chris, as you may recall I am fitting a pair of extension plates to a shorter shock? the plates are long enough to have also raised the overall to 340cm as against the original 320cm, therfore there is an additional thickness to account for on the lower mount of the shock approx 3mm each plate if that makes any sense? and possibly a longer clevis, but will not really know lengths until I have all the componants together on the bench to measure. Also I would like to retain the "good engineering practice" of 2 threads outside of the nut, old fashioned practice but then again I am old haha!
Replacement shock is GSXR 600 K6, reason low cost/readily available fleabay, fully adjustable +++ the only downside is the short length and possible spring rate, if these problems can be easily overcome it gives IMO another good alternative to the very poor stock standard one.
JOHN

[embee]

FWIW this is general rather than specific.

Grade 8.8 is the normal general purpose load bearing grade bolt spec. Higher specs such as 10.9 or 12.10 are usually only used internally (con-rods/main bearings etc) or for machine tools and the like where corrosion will not generally be an issue and they can be left in the natural or phosphated (typically black) finish. Any sort of electroplating will render the untreated grade void, and such things as capscrews (allen screws or bolts) which might be stamped 10.9 in black/oiled finish should be treated as 8.8 at best in BZP (bright zinc plate)/passivated finish.

I would be surprised if the suspension bolts are not equivalent to 8.8. While they are doing a pretty important job, the loads are not enormous in real terms.

IIRC they are 10mm dia, that gives around 70mm^2 of material (less in the threaded region, around 55mm^2 ish), and if you assume a min tensile strength of maybe 600N/mm^2, shear strength can be taken as more or less the same for ductile steels, so single shear is at least 30kN, or around 3 tonnes. Do you reckon that's enough?

Are they a fine thread? I have a feeling they might be (std metric coarse is M10x1.5, fine can be 10x1.0 or 10x1.25)

As said, not a definitive answer but some food for thought.