As requested, here are some insights into understanding the Toyota part number logic for both legacy and current hardware.
There is some back ground to understand though and some of it is easier to understand than other aspects:
For legacy hardware (so basically everything from the 4x time period with a bit of 6x/7x truck legacy), the breakdown of the first 3 digits of the first 5 prefix digits goes like this:
1st condition: will always start with 9
2nd condition: will be a number from 0-9, A-Z
3rd condition: will be a number from 0-9
2nd condition definitions:
0= Standard hardware
1= Hexagonal head bolts
2= Bolt
3= Screw
4= Nut and washers
5= Rivet, pin, key, nail, etc.
6= Fastening plate, fitting seal, cushion, hose clamp
7= Roller bearing (anti-friction)f
8= Tire and tube
9= functional parts
A-Z= serial in meaning and position; usually based on Toyota engineering application as provided by Toyota supplier
3rd condition definitions (a sub-category of the 2nd condition definitions):
900= Manufacturer semi-standard parts (same as 1-9 from 2nd condition but meant for Toyota suppliers)
909= Special semi-standard parts (think 3.5mm vacuum hose: 90999-92003 for example)
911= Hex head bolt (Class 1)
912= Hex head bolt (Class 2)
913= Hex head bolt (Class 3)
914= Hex head bolt (Class 4)
921= Stud
927= Square head bolt, flat head bolt, hex socket head bolt
928= Cup square neck bolt, Flat square neck bolt
931= Slotted screw
932= Cross-recessed screw
935= Cross-recessed tapping screw
936= Slotted wood screw
937= Cross-recessed wood screw
941= Hexagon nut
942= Nut
943= Plate nut
944= Part with nut
945= Spring washer
946= Plate washer
947= Seal washer
951= Rivet
952= Nail
953= Pin
955= Key
961= Fasteners
963= Pipe fittings
964= Fittings
966= Oil seal, dust seal
967= oring
968= cushion
971= single row, deep groove, ball bearing
972= magnet ball bearing
973= angular ball bearing
974= double-row, self-aligning ball bearing
975= cylindrical roller bearing
976= tapered roller bearing (JIS)
977= tapered roller bearing (Timken)
978= spherical roller bearing
980= tire and tube set
981= tire
982= tube
983= rim band
984= flat
985= tubeless tire
991= switches, alarms, lighting equipment, wires, batteries
992= spark plug
So, example: 91112-41220=
91= standard hexagon head bolt
1= hexagon head bolt class 1
1= effective diameter bolt
2= flat threaded end
(-)
4= 4T (bolt tensile strength)
12= Thread diameter 12mm
20= length under head 20mm
Or, put another way:
Hardware part number: "ABCDE-FGHIJ"
AB= Initial digits of semi-standard part number (90xxx series) or standard part number (91xxx through 99xxx series)
C= Item nomenclature description type
D= effective diameter
E= rough finish
(-)
F= tensile strength
GH= thread diameter in mm
IJ= length under head in mm
Now, in the mid-1980's and into the 1990's and continuing today, Toyota part numbering has gotten more and more complicated on the surface.
What has actually happened is that there has been a reduction in part numbers through the process of discontinuation, regionalization of manufacture and part numbering, as well as superseding a number of different part numbers into a new part number (this last one is especially true for semi and standard hardware).
A new part number prefix has also developed that now encompasses many different pieces of hardware with no ostensive logic. These are the 90080 prefix numbers. These are mainly North American manufactured parts (though not exclusively) that replace parts that used to arrive via boat from Japan. So, some examples:
90917-06065 is a down-pipe to manifold "donut" gasket. This is a Japan manufacture part that follows the internal semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-43036. This part number says nothing about the part or where it lives or what it does.
See here this part number as well: 90179-10070 is a lock nut used on down-pipe to manifold mating studs. This is a Japan manufacture part that follows the internal semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-17187. This part number says nothing about the part or where it lives or what it does.
Same for this example: Spark plugs have historically been 90919-XXXXX. So, for example, 90919-01210 is the factory part number (generally called the "engineering part number") for a spark plug for a UZJ100 (2UZ-FE engine) Land Cruiser. This is a Japan manufacture part that follows the semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-91180. This part number says nothing about the part or where it lives or what it does.
Now, when it comes to the 90080-XXXXX part numbers, there is obviously (like everything to do with Toyota) some logic that is internal and is not something that is now available to even Toyota parts professionals. One just has to remember the number and know that it is a supersession of a formerly Japan manufacture part. There is unfortunately no other way to decipher these parts numbers as there is no external, ostensive logic to them.
Anyway, the above is part of a much larger project/document I am working on that explains--in minute detail--the entire Toyota parts procurement, engineering, numbering and application world.
Hope this helps.
Best.
-onur
There is some back ground to understand though and some of it is easier to understand than other aspects:
1. Toyota part numbers are either 10-digits or 12-digits using a combination of numerals and letters (letters come much later on...early 2000's). The hyphen is used for readability.
2. A 10-digit Toyota part number is broken up into two sections: Prefix 5-digit number and suffix-5 digit number. For our purposes in discussion hardware, all of them will begin with 9 and look like this: 9xxxx-xxxxx
3. Hardware specific to different systems (AC, electrical, etc.) will have their own numbers. For example, the AC idler adjusting bolt is 88446-35040. This bolt is not "standard" or "semi-standard" hardware. This bolt is specific to the AC system (88446) and it is even more specific to the R engine family (35040) and is used in the 1FZ-FE engine family as well (a good example of how Toyota re-uses old designs rather than re-design a new part when an old one will work just fine).
Another good example: 81119-1A270: Headlight adjusting bolt (2 per headlight) for an FJ60. The first 5 digits indicate the headlight system (81119). This is a specific piece of hardware manufactured specifically for this application, thus it is out side of the normal scope of standard or semi-standard hardware.
For legacy hardware (so basically everything from the 4x time period with a bit of 6x/7x truck legacy), the breakdown of the first 3 digits of the first 5 prefix digits goes like this:
1st condition: will always start with 9
2nd condition: will be a number from 0-9, A-Z
3rd condition: will be a number from 0-9
2nd condition definitions:
0= Standard hardware
1= Hexagonal head bolts
2= Bolt
3= Screw
4= Nut and washers
5= Rivet, pin, key, nail, etc.
6= Fastening plate, fitting seal, cushion, hose clamp
7= Roller bearing (anti-friction)f
8= Tire and tube
9= functional parts
A-Z= serial in meaning and position; usually based on Toyota engineering application as provided by Toyota supplier
3rd condition definitions (a sub-category of the 2nd condition definitions):
900= Manufacturer semi-standard parts (same as 1-9 from 2nd condition but meant for Toyota suppliers)
909= Special semi-standard parts (think 3.5mm vacuum hose: 90999-92003 for example)
911= Hex head bolt (Class 1)
912= Hex head bolt (Class 2)
913= Hex head bolt (Class 3)
914= Hex head bolt (Class 4)
921= Stud
927= Square head bolt, flat head bolt, hex socket head bolt
928= Cup square neck bolt, Flat square neck bolt
931= Slotted screw
932= Cross-recessed screw
935= Cross-recessed tapping screw
936= Slotted wood screw
937= Cross-recessed wood screw
941= Hexagon nut
942= Nut
943= Plate nut
944= Part with nut
945= Spring washer
946= Plate washer
947= Seal washer
951= Rivet
952= Nail
953= Pin
955= Key
961= Fasteners
963= Pipe fittings
964= Fittings
966= Oil seal, dust seal
967= oring
968= cushion
971= single row, deep groove, ball bearing
972= magnet ball bearing
973= angular ball bearing
974= double-row, self-aligning ball bearing
975= cylindrical roller bearing
976= tapered roller bearing (JIS)
977= tapered roller bearing (Timken)
978= spherical roller bearing
980= tire and tube set
981= tire
982= tube
983= rim band
984= flat
985= tubeless tire
991= switches, alarms, lighting equipment, wires, batteries
992= spark plug
So, example: 91112-41220=
91= standard hexagon head bolt
1= hexagon head bolt class 1
1= effective diameter bolt
2= flat threaded end
(-)
4= 4T (bolt tensile strength)
12= Thread diameter 12mm
20= length under head 20mm
Or, put another way:
Hardware part number: "ABCDE-FGHIJ"
AB= Initial digits of semi-standard part number (90xxx series) or standard part number (91xxx through 99xxx series)
C= Item nomenclature description type
D= effective diameter
E= rough finish
(-)
F= tensile strength
GH= thread diameter in mm
IJ= length under head in mm
Now, in the mid-1980's and into the 1990's and continuing today, Toyota part numbering has gotten more and more complicated on the surface.
What has actually happened is that there has been a reduction in part numbers through the process of discontinuation, regionalization of manufacture and part numbering, as well as superseding a number of different part numbers into a new part number (this last one is especially true for semi and standard hardware).
A new part number prefix has also developed that now encompasses many different pieces of hardware with no ostensive logic. These are the 90080 prefix numbers. These are mainly North American manufactured parts (though not exclusively) that replace parts that used to arrive via boat from Japan. So, some examples:
90917-06065 is a down-pipe to manifold "donut" gasket. This is a Japan manufacture part that follows the internal semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-43036. This part number says nothing about the part or where it lives or what it does.
See here this part number as well: 90179-10070 is a lock nut used on down-pipe to manifold mating studs. This is a Japan manufacture part that follows the internal semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-17187. This part number says nothing about the part or where it lives or what it does.
Same for this example: Spark plugs have historically been 90919-XXXXX. So, for example, 90919-01210 is the factory part number (generally called the "engineering part number") for a spark plug for a UZJ100 (2UZ-FE engine) Land Cruiser. This is a Japan manufacture part that follows the semi-standard part numbering logic. For the US, Toyota superseded the part to a local production part and gave it the following part number: 90080-91180. This part number says nothing about the part or where it lives or what it does.
Now, when it comes to the 90080-XXXXX part numbers, there is obviously (like everything to do with Toyota) some logic that is internal and is not something that is now available to even Toyota parts professionals. One just has to remember the number and know that it is a supersession of a formerly Japan manufacture part. There is unfortunately no other way to decipher these parts numbers as there is no external, ostensive logic to them.
Anyway, the above is part of a much larger project/document I am working on that explains--in minute detail--the entire Toyota parts procurement, engineering, numbering and application world.
Hope this helps.
Best.
-onur
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