Aftermarket Engine Brackets Specification Example for City Buses: Drilled and Slotted
Aftermarket Engine Brackets Specification Example for City Buses: Drilled and Slotted
This is a worked specification for aftermarket engine brackets in a drilled and slotted 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 drilled and slotted version exists because the duty cycle on city buses is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually a supplier who changed material without saying so.

Example specification
| Item | Aftermarket Engine Brackets |
|---|---|
| Application | City Buses |
| Version | Drilled and Slotted |
| Base material | Anodised Aluminium |
| Controlled dimensions | 3 key dimensions, recorded per lot |
| Tolerance band | ±0.1 mm |
| Finish | powder coated |
| MOQ | 200 pieces per specification |
| Sampling | 14 working days, 5 days per revision |
| Compliance | DOT |
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
- heat treatment
- sintering
- precision stamping
- anodising
- injection moulding
- rubber vulcanisation
Where this example applies
Programmes that run drilled and slotted most often specify this build for city buses. Related applications include utility trailers, rental motorcycles, passenger cars, racing teams, municipal fleets.
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
What testing is included?
Standard lots ship with dimensional and hardness reports. DOT documentation is issued with the shipment when your market requires it.
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.
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 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.
Share a sample or a drawing and we will quote against a written specification, not against a photograph.



