Selection scope and sizing decision
Useful for: Fleet buyers who need to translate target vehicles into separate wrecker equipment ratings
A single capacity label can conceal several different ratings. Procurement becomes clearer when every target scenario identifies which component carries the load and where that load acts.
The controlling case may be an axle reaction, extension position, attachment limit, deck load distribution or chassis limit rather than the largest number in a brochure.
Sizing inputs
Supply these values before a model, body size or working rating is selected:
- 01Target vehicle mass and axle distribution
- 02Required carrying, pulling, towing and lifting functions
- 03Working extension and load position
- 04Loading angle and surface condition
- 05Attachment and restraint method
- 06Selected chassis ratings and completed layout
From sizing inputs to model approval
Size from the operating requirement, test the complete configuration and retain the project records that control the final selection.
- 01Define the target duty
Wrecker working-rating selection
- 02Quantify sizing inputs
Target vehicle mass and axle distribution; Required carrying, pulling, towing and lifting functions
- 03Test the complete vehicle
Deck and Winch must both pass.
- 04Approve the selected rating
Manufacturer rating documents and load diagrams; Target-scenario schedule
Selection and sizing matrix
Use every row to test the proposed size. A nominal value is not sufficient when payload, geometry or operating limits conflict.
Scroll horizontally to view all columns.
| Decision factor | What to choose or check | Limit or condition |
|---|---|---|
| Deck | Check carried mass and placement across the usable deck. | Deck rating does not define winch, lift or tow capability. |
| Winch | Check pull requirement, line arrangement and manufacturer conditions. | Winch rating does not authorize towing or lifting. |
| Tow | Check towed target, braking, attachment and road conditions. | Tow rating is not the same as supported lift load. |
| Lift or underlift | Check supported axle load at the working extension. | Capacity can change with geometry. |
Applied calculation
Keep supported load, pull and tow checks separate This example shows the logic for one wheel-lift case without turning a component rating into a whole-vehicle rating.
- 01Lift-chart checkMust pass
Chart capacity at 1,500 mm ≥ 2,100 kg - 02Chassis reaction checkMust pass
Completed rear axle reaction ≤ approved axle limit - 03Attachment checkMust pass
Approved attachment and restraint for the target axle
Decision: The wheel-lift duty is acceptable only if all three checks pass. A winch or headline tow figure cannot replace any one of them.
Evidence boundary: The values are hypothetical. Manufacturer charts, target-vehicle instructions and destination towing rules control the real case.
Selection evidence checklist
Ask for evidence that is traceable to the selected model, configuration, vehicle or project scope. A record from another project is context, not verification.
- Manufacturer rating documents and load diagrams
- Target-scenario schedule
- Completed-vehicle axle-load calculation
- Inspection and functional-test records
Selection and sizing traps
Using the largest published number as vehicle capacity
Better selection method: Identify the controlling rating for each load path.
Ignoring extension or load position
Better selection method: Compare capacity at the actual working geometry.
Treating a test result as a universal operating limit
Better selection method: Use the approved manufacturer ratings and stated conditions.
Limitations
- This guide cannot calculate a project rating without equipment documents.
- Destination towing and vehicle rules require local confirmation.
- Do not operate when the controlling rating, load position or attachment cannot be verified.
Evidence scope and technical basis
Each source is limited to what it can support. This makes the evidence chain readable to buyers, search engines and AI systems without turning a general source into a project claim.
Supports: Controls the project-input, quotation, approval and inspection workflow described in this guide.
Does not establish: It does not replace the signed quotation, approved specification, selected OEM documents or unit-linked project records.
Supports: Provides public checklists and worksheets; the signed project documents remain controlling.
Does not establish: It does not replace the signed quotation, approved specification, selected OEM documents or unit-linked project records.
Supports: Defines the relevant product family and published configuration boundaries. Project-specific ratings require the selected OEM documents.
Does not establish: It does not replace the signed quotation, approved specification, selected OEM documents or unit-linked project records.
Supports: Primary manufacturer example showing that towing-equipment ratings, chassis capacity and operating limits are manual and model specific. It does not provide a KEEYAK project rating.
Does not establish: It applies to the named manufacturer example and does not establish a KEEYAK model rating or project result.