Whether you are a “do-it-yourselfer”, or simply looking to save a few dollars by shopping for your own parts, chances are, as a Porsche owner, you’ve run across those crazy 11 digit numbers (000-000-000-00) that signify the one piece you need for your pride and joy to be perfect again.  What does it all mean?  How do part houses and Porsche dealerships know how to translate the code to get you the parts you need?

As with everything Porsche does, there are no concrete rules, and this post should simply be used as a guideline, rather than taken as the gospel.  That which is true of Porsche today, may be the reverse at any point in the near future.  For the time being, though, we’ll break down the 11 digit numbers into four smaller groups to make them easily digestible.

THE FIRST GROUP OF THREE DIGITS XXX-000-000-00

These are probably the easiest to decipher, but again, there are some extenuating circumstances that can throw you for a loop.  Most Porsche parts use a 3 digit prefix that relate them to a specific model in the Porsche range, usually the one that they were first designed for. However, Porsche has been known to carry these parts on to later models (e.g. 914 emergency brake switches are also used for 968 door light switches).

1. Standard model prefixes include 901, 902, 911, 930, 914, 928, 964, 986, 996, etc. which usually correlate to the model on which you will find them.

 

1. 999, 900, or N prefixes generally denote hardware components with multiple uses.

 

1. As the 914-4 used a Volkswagen derived “type-4” engine, there are many VW part numbers used, 022, 021, and 113 are common prefixes for these parts.

 

1. The 924/944/968 trio of cars were originally developed for use as a new Volkswagen sportscar using existing components such as the Audi 2.0 liter engine, VW MK1 derived front suspension, and VW Super Beetle derived rear suspension.  As such, many of these components use VW part numbers.

 

1. The automatic transmission found in the 928 is a model that was developed with Mercedes Benz, and uses their part numbering system, with prefixes like 115, 126, and 722 to show for it.

 

1. Transmission or Engine parts can often receive their own prefix based on the number of that engineering exercize – 915, 741, 547, 950, etc.

THE SECOND SET OF THREE DIGITS 000-XXX-000-00

Moving on we get to the meat of the part number.  The first number in this second series of three digits signifies the section/system of the Porsche where the part can be found (i.e. Engine, Transmission, Front Suspension, Rear Suspension, etc.). The final two numbers in the series are related to the diagram number, within Porsche’s PET system, on which they can be found (PET is the internal system of diagrams used for seeking out an individual part, most often found at dealership part counters).  After some digging, this seems to be more based on coincidence than actual fact, but it seems that as the second and third digits increase in value, the part is found deeper in numerically higher diagrams. Using the below outline, I’ll explain which numbers correlate to which system, and list a few of the components that can be found there.

1. 100 – Engine
   1. Rotating assembly, Flywheel, Case and Cylinder Head related components

    

2. 200 – Fuel and Exhaust
   1. Fuel Tanks, Pumps, Lines, Regulators
   2. Mufflers, manifolds, gaskets, tips, turbochargers

    

3. 300 – Transmission
   1. Clutches, Pressure Plates, T/O bearings, internal components, mounts, clutch slave cylinders

    

4. 400 – Front Axle/Steering
   1. Front wheel bearings, wheel seals, uprights, hubs, lug studs, suspension components
   2. Steering wheel, steering rack components, column mounted switches.

    

5. 500 – Rear Axle
   1. Drive axles, rear wheel bearings, trailing arms, rear wheel bearings, hubs, lug studs

    

6. 600 – Wheels/Brakes
   1. Wheels, center caps, spacers, lug nuts, master cylinder, calipers, pads, rotors

    

7. 700 – Levers/Pedals
   1. Accelerator, clutch, and brake pedal assembly, accelerator and clutch cables, clutch master cylinders
   2. Hood, trunk, fuel door, and engine cover release cables
   3. Transmission control levers and linkages

    

8. 800 – Body
   1. Sheetmetal, trim, emblems, decals, interior components from upholstery to hardware, all HVAC components

    

9. 900 – Electrical
   1. Engine ignition system (distributor, coil, plugs and wires), alternators, starters, windshield wiper and washer system, ignition and dash switches, electric motors, in-car entertainment, lighting

THE THIRD SET OF THREE DIGITS 000-000-XXX-00

These are an internal code for the “actual number of the part”.  This does not seem to have any significance to the end user, perhaps this is based upon the engineering project number for that specific piece, or perhaps it has no significance at all.  As far as we, the people buying the parts, are concerned, the number could have been pulled from thin air after a long liquid lunch at the local biergarten.

THE FINAL TWO DIGITS 000-000-000-XX

These are known as the “modification number”.  For the most part, Porsche produced parts end in a pair of zeros.  When you see something other than these two zeros it means there has been a modification to the piece from its original production run.  This could me a minor change in the material specification, or even a significant change in the exterior dimensions of the part.  Either way, each subsequent modification will receive a new part number with an incrementally higher modification digit.  Often, these modifications are completed before the part is even installed on a production-line automobile; however, occasionally there are super sessions that will replace an earlier number.

This knowledge has been gleaned through several years in the Porsche parts industry, and thousands of hours spent poring over physical parts, as well as the PET system’s signature black and white outline drawings.  While PET access is generally limited, Porsche themselves have allowed free access to a PDF version of the catalog, as a resource for owners of Porsche models produced before 1998.