“Will this fit a Mercedes A Class?” is a question nobody can answer, because there is no such thing as one A Class. There is a W176 and a W177, and a bumper for one will not go near the other.
Manufacturers do not change the model name when they change the car underneath. They change the chassis code. Learn to read yours and buying parts stops being guesswork.
What is a chassis code?
A chassis code is the manufacturer's internal name for a specific generation of a specific platform. The marketing name stays the same for decades; the chassis code changes every time the car is genuinely redesigned.
Volkswagen have sold a Golf since 1974. There have been eight of them. A splitter for a MK7 and a splitter for a MK8 share a name and nothing else.
How each manufacturer writes them
| Make | Format | Examples | Reads as |
|---|---|---|---|
| Mercedes | W / C / S / X + three digits | W176, W205, C117, X253 | W = saloon or hatch, C = coupé, S = estate, X = SUV |
| BMW | E, F, G or U + two digits | E46, F20, G20, G80 | E is oldest, then F, then G. Higher letter is newer |
| Audi | Letter + number, or B / C series | 8V, 8P, B8, C7 | 8-series for small cars, B for A4, C for A6 |
| Volkswagen | MK + number | MK5, MK7, MK7.5, MK8 | Sequential. The .5 is a facelift, not a new car |
| Ford | MK + number | Focus MK2, MK3, MK4 | Sequential |
| Land Rover | L + three digits | L322, L405, L494, L461 | Per model line |
Why a facelift is not a new chassis, except when it is
This catches people out constantly.
A facelift (LCI in BMW language, “.5” at VW) changes bumpers, lights and interior trim on the same underlying car. Suspension and brake parts usually carry over. Body parts usually do not — a pre-facelift front splitter will not fit a facelift bumper.
A new chassis code means a new platform. Almost nothing carries over.
So for suspension or brakes, the chassis code is usually enough. For body styling and grilles, you need the chassis code and whether it is pre- or post-facelift.
How do I find my car's chassis code?
- Check the V5C. The registration document lists the model variant, which often includes it.
- Check the build plate. Usually in the door shut, the boot floor, or under the bonnet.
- Work from the year and model. A 2016 A Class is a W176. A 2020 A Class is a W177. The changeover years are the ones to be careful about — a car registered in the changeover year could be either.
- Ask us. Send the registration and we will tell you.
The changeovers worth knowing
- Mercedes A Class – W176 to 2018, W177 from 2018
- Mercedes C Class – W204 to 2014, W205 to 2021, W206 from 2021
- BMW 3 Series – E90 to 2012, F30 to 2019, G20 from 2019
- BMW 1 Series – E87 to 2011, F20 to 2019, F40 from 2019
- Audi A3 – 8P to 2012, 8V to 2020, 8Y from 2020
- VW Golf – MK6 to 2012, MK7 to 2017, MK7.5 to 2019, MK8 from 2019
- Ford Focus – MK2 to 2011, MK3 to 2018, MK4 from 2018
Where this bites: bolt patterns
Chassis changes sometimes bring a change of bolt pattern, which affects wheels and spacers as well as body parts. Mercedes moved from 5×112 across most of the range. Audi and VW use 5×112 on larger cars and 5×100 on some smaller ones. BMW moved from 5×120 to 5×112 on newer models.
This is why a wheel that fitted your last car may not fit this one, even though both are the same make. Our 5x112 guide covers which cars use it, and the spigot rings guide explains centre bore, which changes independently of bolt pattern.
For spacers specifically, bolt pattern, centre bore and thread pitch all have to match — see our wheel spacer guide.
Finding parts for your chassis
Rather than searching a model name and sorting through results for the wrong generation, use the car picker on our performance parts page. Pick the make, pick the model, and it filters to parts tagged for that car. Nothing else appears.
From there you can narrow by what you are actually after:
- Body styling and aero – splitters, diffusers, skirts, spoilers
- Exhausts and induction – downpipes, decats, back boxes, induction kits
- Brakes and discs
- Intercoolers and charge cooling
- Coilovers and suspension
- Grilles
If you take one thing away
When you ask about a part, give the chassis code and the year, not just the model name. “A Class” could be either of two cars. “W176, 2016” is one car, and we can answer it in a sentence.