What will it cost to send this part?
Two things decide the bill, and only one of them is the weight. Put in the size of the packed box and this gives you the weight the carrier will actually charge you for, the exact Australia Post price between capital cities, and a straight answer when the part is too big for anyone to price from a website.
Measure the PACKED box, not the part. Tape, padding and a pallet all count, and the depot re-measures.
You will be billed for 12kg
Actual weight 12kg, cubic weight 6.75kg. Carriers bill whichever is greater. This one is priced on its weight.
$37.75
Australia Post Parcel Post price for a parcel of exactly these dimensions, Adelaide to Sydney, own packaging. Price as at 2 August 2026.
Add 5cm to the longest side and it becomes $37.75. That is what the packaging costs you.
That opens Australia Post with both postcodes filled in. You will need to re-enter the size and weight: their calculator keeps those in the page, not in the link, so nothing we put in the URL would carry them across.
We are not the carrier and we are not part of this sale. These are Australia Post retail prices for a parcel you describe, read on 2 August 2026; carriers re-measure at the depot and bill the difference. Business account rates are lower and are not shown here. Wheel offset calculator if you are checking fitment before you buy.
Reading the answer
Cubic weight is what catches people
Carriers charge for the space a parcel takes on a truck as well as its mass, and they bill whichever number is bigger. A set of four wheels is not expensive to send because it is heavy. It is expensive because it is enormous.
The practical consequence is that packaging is not free. Adding five centimetres of padding to the longest side of a box can push it over a whole-kilogram boundary and add real money, which is why this page shows you that number directly rather than making you guess at it.
Why some routes show no price
The tariff read here covers the capital-city lanes. Outside them the rate moves far too much to interpolate: from Perth, a parcel to Adelaide is $3.85 a kilogram and the same parcel to Mount Gambier is $7.45. Guessing the difference would put the total out by most of its value, so those routes get the chargeable weight and a link to the carrier instead of a number we would be inventing.
Why a gearbox has no price at all
Anything over 22kg, longer than 105cm, or bigger than a quarter of a cubic metre leaves the parcel network entirely and becomes road freight. There is no published retail tariff for that in Australia. Rates are account-specific, and the oversize surcharge on a single carrier can span more than the entire base cost of a metro pallet. A number here would be fiction.
What actually helps is getting quoted once instead of five times. Freight desks ask the same questions every time, so the page gives you the answers in a block you can paste into an email. If you are shipping a half cut or a rolling shell, the reverse-auction boards are usually cheaper than ringing carriers one at a time.
Common questions
Why is my parcel priced on size instead of weight?
Carriers bill whichever is greater, the actual weight or the cubic weight. Cubic weight is length times width times height in metres, times 250 for Australia Post. A bucket seat is the clearest case: it weighs about 12kg, well under the 22kg limit, and it is still out of the parcel network entirely because a boxed one is over a quarter of a cubic metre. Weight was never the thing stopping it.
Does a 1kg parcel really cost less than a 1.01kg parcel?
Yes, and the gap is enormous. Australia Post does not apply cubic weight at or below 1.00kg actual. The same 60 x 50 x 40 box from Perth to Adelaide is $16.00 at 1.00kg and $120.70 at 1.01kg. If you are near that line, it is worth weighing the packed box properly.
How much does it cost to post a gearbox or an engine?
There is no honest online answer. Both are over the 22kg parcel limit, so they move as road freight, where every rate is account-specific and the oversize surcharges vary more than the base cost. What helps is asking for the quote properly: dimensions, weight, whether it is drained of fluids, and whether there is a forklift at each end. This page gives you that block to paste.
What is the biggest parcel Australia Post will take?
22kg actual weight, no side longer than 105cm, and strictly under a quarter of a cubic metre. Note that cubic weight is not capped at 22kg: a light, bulky parcel is still accepted and still billed on its size, which is where most bill shock comes from.
Can I book the freight through this site?
No, and deliberately. We are not the carrier and we are not part of the sale. Taking freight money without controlling the shipment is how a buyer pays and never receives anything. The links here hand you to the carrier's own booking, where you pay them directly.
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