Allow me to explain a few things guys:
1. Manufacturers group vehicles by Chassis family, not by year, not by engine & not by retail models etc - which means in Subaru's Fast the "GC" (actually G10 chassis) catalogue covers ALL GC/GF/G3/G5 etc from 92-2000 - so a vin IS required to exclude the other G10 chassis items that aren't fitted to your specific chassis....So say I went looking for a 'GC' sway bar bush (for example) in Subaru's FAST parts system with no vin, the system will list ALL the sway bar bushes used over the chassis's entire lifespan, for all variants (wagon,Gx,lx,Sti,FWD & wrx) maybe 7 or 8 different part numbers, it won't tell me the dimensions,colour, part number specific differences, year range of use etc...It just doesn't work that way, Don't blame the guy using the system....We DIDN'T design it!
2. Parts interpreters can't be expected to know EVERY part on EVERY vehicle.....50,000 unique part numbers per model just aint gonna happen....Even if it is just a crush washer for a sump plug....it still has a 7-13 digit part number that we need to locate via the catalogue....Which means a VIN is required. Nissan for example has 12 commonly used sump washers..... across all of their engines. Odds are 1 in 12 for guessing the correct 1 for you?
3. What would take 30 seconds to find with a VIN number in the system, may take 5 minutes to find without one - & that shits us.
4. They're not all the same..... regardless of what you may think!
5. Re-read #4.
There are short cuts to this system but they do allow inaccuracy to creep in.
YOU can use
www.opposedforces.com to find your own part numbers, They may be correct, they may not..... I'd err on the side of caution myself.
The interpreter may keep some generic year/model/motor vin's on hand (I do this) to assist people with no idea what their VIN is...For those "Um, mate it's just a GU Patro/D40 Navara/Getz/xtrail/Sonata/i30/skylinel" moments.
Think of your VIN as the Password to access your specific car's details, it's a simple as that. It takes YOU 30 seconds to write down your vin for a parts guy & I don't think it's too much to ask... I keep my vin in my phone, pretty simple.
Plus it saves you:
Time - the parts guy is looking at your specific chassis.
From getting the wrong parts - as only what was fitted OEM to your chassis is listed with part numbers.
And it stops the interpreter pulling his hair out in pure frustration from hearing "It's just a xxxx, they're all the same, how hard can it be? there's millions on the road" for the 100th time today.
Trust me it isn't as easy as you may think....
I've done Nissan,Toyota,Ford,Holden,Bmw,Porsche, Bentley, Rolls Royce, Chrysler, Mazda, Jeep, Dodge,Hyundai & Daihatsu from an OEM parts supply view point......Regardless of cataloge system used by them (Microcat, Partfinder, Etk, Piwis, Fast parts, etc), the common thing amongst them all is their catalogues require a VIN to be accurate.
End of explanation.