Car Door Assembly Specification Example for Aftermarket Retail: Vented Design
Car Door Assembly Specification Example for Aftermarket Retail: Vented Design
This is a worked specification for car door assembly in a vented design programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The vented design version exists because the duty cycle on aftermarket retail is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually packing that arrived crushed at the port.
Example specification
| Item | Car Door Assembly |
|---|---|
| Application | Aftermarket Retail |
| Version | Vented Design |
| Base material | Polypropylene |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | zinc plated |
| MOQ | 500 pieces per specification |
| Sampling | 14 working days, 3 days per revision |
| Compliance | SAE J431 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Polypropylene, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.
Processes involved
- heat treatment
- anodising
- robot welding
- ultrasonic cleaning
- rubber vulcanisation
- die casting
Where this example applies
Programmes that run vented design most often specify this build for aftermarket retail. Related applications include three-wheelers, boat trailers, fleet maintenance, utility trailers, delivery vans.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 2.5 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 500 pieces per line.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
How long does sampling take?
Samples leave the factory in 14 working days, and each revision round adds about 3 days once you have seen the first piece.
Can you match an existing sample?
Send a sample and we will reverse-engineer the specification, then produce a counter sample for approval before any bulk starts.
Tell us the model, the fitment and the quantity and we will hold a production slot for you.
