Which aftermarket car parts belong in a 3D viewer

Selling car parts online runs on fitment data. The customer has one particular car, the part fits it or it doesn't, and the trade keeps databases that map part numbers to vehicles. When that mapping is wrong, the part comes back.

A 3D viewer doesn't replace any of that. No model can tell you whether an ET45 offset clears your brake calipers. Where it helps is with a different set of questions, the ones a fitment database has no field for.

Compatibility and suitability

The first question is compatibility: will the part bolt to my car? That covers bolt pattern, offset, hub bore, thread pitch, mounting points and the electrical connector. It's catalogue work. It has to be exact and searchable by registration or by make, model and year, and 3D doesn't change it.

The second is suitability. The part fits, but does the buyer want it on their car? They want to know how big it is in real life, how the finish looks in daylight, whether the roof box will hit the garage door, whether the wheel goes with the paint and how far the tow bar sticks out.

Shoppers hesitate over that second list. A parts site that has compatibility sorted and leaves suitability out sends people to forums, looking for photos of the part on someone else's car.

Alloy wheels

Wheels are the clearest case in the aftermarket. Once a wheel is known to fit, the choice is mostly about looks, and it comes down to spoke design, finish and depth, which are hard to photograph.

In a 3D viewer the customer can turn the wheel, look at the spoke profile from an angle and switch between gloss black and satin gunmetal on the same geometry, under the same light. Finishes are usually photographed separately, on different days and in different light, so shoppers can't compare them properly from the photos.

A wheel on its own still doesn't show how it looks on the customer's car. Some retailers use a 2D visualiser that pastes the wheel onto a photo of the vehicle. That helps with the look but says nothing reliable about size, because it's a flat image laid over a photo. A 3D car configurator puts the wheel on a model of the car. On our demo coupé the rims are separate parts and each finish is a material, as described in how a car configurator works.

Roof boxes and garage clearance

People buying a roof box have usually never owned one, and they ask the same two things: how far does it stick out, and will the car still fit in the garage?

AR helps here in a way a photo can't. Both phone platforms can place a model at true scale straight from the browser. On Android that's Scene Viewer, where one glTF unit is one metre, so the model shows at its real size. On iOS it's AR Quick Look in Safari. A customer can stand in the garage, put a 175 by 82 centimetre box in the air at about roof height and see how close it comes to the ceiling.

The 3D viewer on the product page does a simpler version of the same job. It draws dimension lines on the model and shows which way the lid opens and how far it swings up. Few product pages list the lid swing, although it decides whether the box can be opened in a low car park.

Tow bars, side steps and bull bars

Anything that sticks out past the bodywork raises the same worries. Buyers want to know how far it goes, whether it covers the number plate or the parking sensors, whether the boot still opens and whether they'll catch their shins on it.

A 3D model of a detachable tow bar can show the neck both detached and mounted, with the projection measured on it. Side steps need two views: one from the end, showing how far they stand off the sill, and one from below, showing the mounting brackets. Product photos in this category rarely include either angle.

Which parts to model first

Filters, brake pads and other consumables are bought by part number, and they make up a large share of an aftermarket catalogue.

Starting with one part

A good first model is the wheel or roof box that brings in the most emails before people buy. Go through those emails for the dimensions and angles people keep asking about, then send the part through the sample page with photos and measurements so the viewer can show them. Prices are per product, so the rest of the high-priority rows can be added one category at a time.

Returns

The National Retail Federation put US returns at 743 billion dollars in 2023, 14.5 percent of sales, and 17.6 percent of online sales. For a parts retailer, a wheel or a tow bar sent back because it looked different or didn't clear something costs shipping in both directions, and it may need restocking with a scuff on it.

One wheel model in several places

A wheel model built once can go into the 3D viewer and a car configurator (both on our solutions page), and the same file renders ad images, print catalogue pages and graphics for a trade stand. Adding a colourway means changing a material on the model and rendering it again. Furniture works the same way: MELIMELI sells sofas in many upholstery options and Sweef sells modular layouts, each from one model per product.

Sources

• Google, Scene Viewer documentation.
• Apple, AR Quick Look.
• Shopify, merchant data on 3D and AR content, September 2020.
• Shopify, AR shopping: Rebecca Minkoff and Gunner Kennels results.
• National Retail Federation and Appriss Retail, 2023 Consumer Returns in the Retail Industry.