A bolt can look perfectly content sitting on the bench while its service instructions are asking for a replacement. I do not make that decision from appearance alone. The 2016 workshop information gives me a useful set of default rules for fasteners, seals, gaskets and adhesive-mounted exterior trim. The trick is remembering which instruction gets the final say.
I read the individual procedure first. Its specific instruction takes priority over these general replacement rules.
Before I reach for a tool
I read the whole job first. Then I get the car, the parts and myself ready.
- Identify the exact vehicle configuration and service procedure
- Read all applicable health and safety precautions before any work
- Check the procedure for replacement-part and fastener instructions before disassembly
- Keep each removed part identified with its location
The actual procedure decides the job
These are the 2016 publication’s general practices, which apply unless the individual procedure says otherwise. I use the complete job instructions, including its warnings, measurements and tightening sequence. This learning reference does not supply a removal procedure.
My decision order starts with the specific job
Find the instruction for this component
I identify the service procedure for the actual component and vehicle configuration. I look for explicit instructions to replace or reuse the part.
Apply that instruction first
If the individual procedure gives a rule different from the general practices below, I follow the procedure’s specific direction.
Use the general rule where it applies
When the procedure does not specify otherwise, I use the appropriate rule in the table. I keep any inspection and preparation requirements from the full job alongside it.
My small-parts decision table
That first row is a general rule for a standard fastener. It is not a reason to ignore damage, discard instructions or the checks in the individual repair. The other rows are a useful reminder to plan the replacement parts before everything is apart.
Self-locking can happen in several ways
Seven locking designs
1 · Fully coated bolt
2 · Partly coated bolt
3 · Bolt with locking washer
4 · Nut with plastic insert
5 · Nut with three indentations
6 · Oval-deformed nut
7 · Nut with integrated locking ring
The source identifies seven examples. Some use a specified coating; others use a mechanical locking feature. I identify the actual fastener from its part and procedure information. A random colored patch, an ordinary washer or a familiar-looking nut is not enough to establish the design.
| Example in the workshop reference | Feature I need to recognize |
|---|---|
| Completely coated self-locking bolt | The specified self-locking coating |
| Partially coated self-locking bolt | A defined area of self-locking coating |
| Self-locking bolt with a locking washer | The specified bolt-and-locking-washer arrangement |
| Self-locking nut with a plastic insert | A plastic locking insert |
| Self-locking nut with three indentations | Thread deformation associated with three indentations |
| Self-locking nut deformed to an oval | An oval form used for thread locking |
| Self-locking nut with an integrated locking ring | A locking ring incorporated into the nut |
I let the part specification make the decision. The bolt’s excellent bench-side manners are a lovely extra.
From my Atlas notebook
Degrees are an instruction, not a decoration
A torque-angle requirement includes a specified number of degrees of rotation. I keep that angle with the rest of the tightening sequence. The 2016 general rule calls for replacement of fasteners carrying such a specification, unless the individual procedure states otherwise.
I do not turn that into “use any new bolt and tighten it by feel.” I still need the correct fastener and the actual procedure’s torque, angle and sequence. This article deliberately has no generic tightening number, because the number belongs to the specific joint.
The sealing edge and the trim adhesive count too
For seals and gaskets, the general practice is replacement unless the specific procedure gives a different instruction. I treat that requirement as part of the job, rather than an optional flourish at the end.
The same default applies to exterior trim attached with glue or adhesive tape. That is a rule about those adhesive-mounted trim parts; I do not extend it to every piece of exterior trim or invent an adhesive-removal technique from it. The component’s own procedure provides the removal, surface preparation and installation details.
What I check before wrapping up
- I have checked the actual procedure for exceptions
- I know which parts and fasteners require replacement
- I have kept the correct tightening values and sequence with their component
- The specified replacement parts are available before assembly
Sources & editorial notes
Original Atlas writing and independently drawn illustrations, based on the technical facts below. First-person comments express editorial judgment, not a claim of hands-on testing. Applicability follows the cited edition.
- 2016 workshop publication, section 100-00: safety cross-reference, standard practices and seven self-locking-fastener examples2016_Mustang_Shop_Manual.pdfPDF file pages 1, 4, 5 · counted from the first PDF page, which may differ from printed page numbers
This guide covers the topic and vehicle configuration stated above. The source register tracks the developing library; the full four-PDF collection has not yet been re-authored.