The wheel rim 'offset' is the distance between the centre line of the rim and the faceplate that bolts onto the hub. It is important to know as different offsets will alter the distance between the inside edge of the rim and the side of the trailer or caravan. It could also increase the overall width of the axle and it may also alter the capacity of a suspension system.
This diagram shows the dimension of the 'Offset' usually measured in millimetres.
When the centre line is the same as the mounting plate line then it has a Zero or No offset.
If the rim has an offset it is usually marked on the front of the rim, near the mounting holes, an example would be:-
ET30 would be a 30mm offset.
ET20 would be a 20mm offset.
Simple way to measure the wheel rim Offset
Start by placing the rim on a level surface with the front of the mounting plate facing upwards, then measure the distance 'A' (in millimetres) from the mounting plate edge to the surface.
Turn the rim over and measure the distance 'B' again as above.
Take distance B from A and divide by 2, this will give you the offset. If the result is a minus number then you have a Negative Offset. Rims with a negative offset are not usually found on trailers and caravans.
Please note: that if the rim edge is not flat on the surface when measuring B (due to the bulge in the rim) then the distance between the surface and the rim edge needs to be deducted from B before making the calculation.
Very well packed and arrived quickly and undamaged. Tyres fitted no problem at a local dealer.
Rated 5 out of 5
steve mobbs (verified owner)–
Great service top price , fast delivery , thank you all , will be my main supplier now for all my wheels ,
Rated 5 out of 5
Malcolm Rendle (verified owner)–
After a long search for a spare wheel for my Caretta teardrop caravan, I found virtually the perfect one on Western Towing’s website thanks to their PCD calculator. Up until then I had been getting a wrong measurement which had made finding an appropriate wheel nigh impossible. The only minor issue was that there was a 2 mm difference in offset. To clarify tthat the wheel would fit I contacted Western Towing for some advice and they were very helpful. The wheel arrived quickly and once the local tyre centre had supplied a tyre found the wheel fitted well. A very reasonable price, when I compare it to what the Caretta dealer was offering, a spare steel wheel with tyre for over £400. I would have no hesitation recommending Western Towing to anybody looking for parts for their trailer or caravan.
Have a question about our Wheel Rim 14 inch 4 stud 100mm? Our sales team are here to help Monday to Friday 9am to 5.30pm. Why not call us on 01392 216336.
Andy (verified owner) –
Very well packed and arrived quickly and undamaged. Tyres fitted no problem at a local dealer.
steve mobbs (verified owner) –
Great service top price , fast delivery , thank you all , will be my main supplier now for all my wheels ,
Malcolm Rendle (verified owner) –
After a long search for a spare wheel for my Caretta teardrop caravan, I found virtually the perfect one on Western Towing’s website thanks to their PCD calculator. Up until then I had been getting a wrong measurement which had made finding an appropriate wheel nigh impossible. The only minor issue was that there was a 2 mm difference in offset. To clarify tthat the wheel would fit I contacted Western Towing for some advice and they were very helpful. The wheel arrived quickly and once the local tyre centre had supplied a tyre found the wheel fitted well. A very reasonable price, when I compare it to what the Caretta dealer was offering, a spare steel wheel with tyre for over £400. I would have no hesitation recommending Western Towing to anybody looking for parts for their trailer or caravan.