4WD Accessory Weight Planner
Plan your accessory build before you buy. Start with an accessory mass tally. Optionally model axle changes using actual load positions, measured baseline axle masses and the applicable ratings.
Start with your own list or load the labelled fictional example. Add only masses absent from your starting weight. Axle modelling is optional and requires actual distances; a position category alone never supplies a front/rear split.
Four longitudinal zones — roof loads also need a measured position
Wheelbase and the load’s actual longitudinal centre of mass determine the static axle changes. Towball downloads add weight to the rear while levering weight off the front.
Interactive Accessory Planner
Add accessories from the catalog or enter your own. Each line is fully editable — adjust the weight, brand/product, load position and source confidence. Results update live.
Start with your accessory list
- Add only items absent from your starting vehicle weight. Replace catalogue estimates with the fitted masses.
- Use a negative-mass line for a removed component. You can total masses without any axle geometry.
- For axle changes, open the optional geometry inputs and enter a distance for each load. For total axle checks, add measured baseline axle masses and ratings.
No accessories added yet.
Common accessory weights & positions
| Accessory | Illustrative Starting Mass (kg) | Load Position |
|---|---|---|
| Bullbar | ~70 | Front |
| Winch | ~38 | Front |
| Snorkel | ~5 | Front |
| Underbody Protection | ~35 | Centre |
| Side Steps / Rock Sliders | ~25 | Centre |
| Suspension / GVM Upgrade Hardware | ~20 | Centre |
| Roof Rack / Platform | ~30 | Roof |
| Rooftop Tent | ~55 | Roof |
| Awning | ~12 | Roof |
| Long-Range Tank (empty) | ~30 | Centre |
| Long-Range Fuel (extra) | ~70 | Centre |
| Dual / Aux Battery | ~25 | Rear |
| Lithium Battery System | ~20 | Centre |
| Canopy | ~100 | Rear |
| Drawer System | ~50 | Rear |
| Fridge / Slide | ~25 | Rear |
| Rear Bar | ~35 | Towbar |
| Spare Wheel Carrier | ~15 | Towbar |
| Towbar / Hitch / WDH | ~25 | Towbar |
| Recovery Gear | ~20 | Rear |
| Water Tank (full) | ~40 | Rear |
These are fictional starting estimates, not verified weights for a particular product. Replace each with the fitted mass and its actual centre-of-mass distance. Fitment location can differ by vehicle.
Total accessory weight
Add up every item to see how much payload is consumed before passengers and cargo.
Axle distribution
Where weight sits matters. Loads ahead of the front axle unload the rear; loads behind the rear axle unload the front. Canopies can span zones: use their actual centre of mass.
Use the free 4WD Weight & Payload Calculator to build your full accessory list with vehicle data. For broader accessory and modification planning, consider the $149 Complete Vehicle Build Assessment. For deterministic axle modelling using your measured baseline and distances, use the $29 Detailed Weight Distribution Calculator & Report.
Calculations use manufacturer-published specifications and Australian road authority reference material, with vehicle details organised by model year, configuration and modification status.