I didn’t say they were sorted for production. I said they arrive in many different lengths. Not said was each of those various lengths have a specific part number and callout code (2 character tag for immediate i.d.) that indicates their design load in a given rate family. I.e. compressed to the dimension X mm’s, the measured load is Y +/- T kg with the rate K kg/mm. Each is specifically in sequence matching the car build sequence very much as you said.
I was the engineer who created that specification control drawing for the spring as well as the “strut module” consisting of the mount, spring, bearing, strut and spring with yet another assembly part number and callout code (usually 3 characters). And I recommended service releases for each car lines which didn’t include all of the spring part numbers because some were never or rarely used.
So we effectively agree, Sorry for the confusion.
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Yeah, that fat spring wire tells the tale. Stiffer spring = the added weight doesn’t compress it as much as the smaller wire spring. That keeps the nose up with the plow on.
I don’t think we’re really disagreeing. Generally the assembly drawing will specify the callout code in the list of materials in its parts list block. The spring (part) drawing will list the variations of the particular spring. I think we’re really only describing the same control protocol differently. I used to call these “piece-part drawings”, because most people didn’t understand the difference between a part drawing and an assembly drawing.
Apologies for misunderstanding the first point in your post. I understood it to mean that springs were sorted post-receipt based upon something other than that defined by the drawing (we used to call them “part suffixes”, but that’s really just semantics). I pictured assemblers hand picking springs on the production line. I can see now that my understanding of the post was incorrect.
I do believe your description of “quick strut” aftermarket manufacturers using a limited number of springs for different applications based largely (maybe solely) on their dimensions is spot-on. For those that get the ones that work, I suppose the quick struts are fine. I cannot imagine one of these quick-strut manufacturers doing anything other than to keep their parts inventory as low as possible.
fyi, some parts stores will install new dampers ( that you buy there) on your old springs for you. Just bring the old stuts with you when you buy the new dampers is all you need to do. My local inde auto parts store provides this service to their customers. I think there is a small fee. From the diy’ers point of view it’s the same as buying quick struts, except you keep the original oem springs in service.