Adjustable Rear Suspension Specification Example for Trailer Axles: Racing Spec
Adjustable Rear Suspension Specification Example for Trailer Axles: Racing Spec
This is a worked specification for adjustable rear suspension in a racing spec 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 racing spec version exists because the duty cycle on trailer axles is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually lead time that slipped twice before bulk started.

Example specification
| Item | Adjustable Rear Suspension |
|---|---|
| Application | Trailer Axles |
| Version | Racing Spec |
| Base material | Anodised Aluminium |
| Controlled dimensions | 4 key dimensions, recorded per lot |
| Tolerance band | ±0.5 mm |
| Finish | as machined |
| MOQ | 3,000 pieces per specification |
| Sampling | 7 working days, 3 days per revision |
| Compliance | IATF 16949 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Anodised Aluminium, 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
- sintering
- powder coating
- rubber vulcanisation
- robot welding
- cold forging
- die casting
Where this example applies
Programmes that run racing spec most often specify this build for trailer axles. Related applications include trailer axles, workshop replacements, construction equipment, aftermarket retail, export programmes.
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
How long does sampling take?
Samples leave the factory in 7 working days, and each revision round adds about 3 days once you have seen the first piece.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the IATF 16949-compliant build instead of a fresh interpretation.
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.
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 3000 pieces per line.
Send the specification you are working to and we will confirm what we can match, what we would change and why.



