Diesel Engine Parts Specification Example for Long-Haul Trucks: Sealed Unit
Diesel Engine Parts Specification Example for Long-Haul Trucks: Sealed Unit
This is a worked specification for diesel engine parts in a sealed unit 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 sealed unit version exists because the duty cycle on long-haul trucks is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually a fitment that looked right on paper and failed on the bench.
Example specification
| Item | Diesel Engine Parts |
|---|---|
| Application | Long-Haul Trucks |
| Version | Sealed Unit |
| Base material | Reinforced Nylon |
| Controlled dimensions | 3 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | painted |
| MOQ | 200 pieces per specification |
| Sampling | 10 working days, 5 days per revision |
| Compliance | RoHS |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Reinforced Nylon, 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
- powder coating
- laser cutting
- surface grinding
- injection moulding
- heat treatment
- ultrasonic cleaning
Where this example applies
Programmes that run sealed unit most often specify this build for long-haul trucks. Related applications include three-wheelers, emergency vehicles, export programmes, scooter fleets, rental motorcycles.
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 200 pieces per line.
What is the minimum order quantity?
The standard MOQ is 200 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
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.
How long does sampling take?
Samples leave the factory in 10 working days, and each revision round adds about 5 days once you have seen the first piece.
Tell us the model, the fitment and the quantity and we will hold a production slot for you.
