The W123, built from 1976 to 1986, earned its reputation for longevity honestly. Engines run for hundreds of thousands of miles and the bodies, when looked after, last just as well. But even the toughest interior plastics have a lifespan, and the youngest W123 is now around forty years old. For many owners the interior trim is now the main thing standing between a good car and a great one.
What forty years does to W123 plastics
W123 interior plastics were hard-wearing when new, but age makes them brittle. Screw caps and covers, which were designed to be pushed in and left alone, are the first to go — they crack the moment someone removes them for access. Kick panels and lower dashboard trims suffer from feet and from years of being stood on during cleaning. Door inserts and switch frames take a daily beating from hands.
Because these parts are cheap individually, they are often replaced last, but they make a disproportionate difference to how a cabin looks.
Small fixings that make a big difference
The trim screws and caps on a W123 are a good place to start. Missing caps leave bare screw heads and holes on display, and once one is lost the rest tend to follow. We list the under-dash kick panel screw caps as a set of four and the lower dashboard plastic screw in several colours, so you can match your interior.
Both are good examples of how Mercedes-Benz shared parts across ranges: the lower dashboard screw is common to the W123, W126 and R107. If you run more than one classic Mercedes, it is worth checking whether the same small parts fit both.
Doors and switches
The W123 door insert is supplied for either side and is one of the most visible pieces of the door card. The window switch frame is shared with the W124, W201 and G-Class, which is useful to know when you are searching for it — a listing for a different model may still be exactly the part your W123 needs, provided the number matches.
The C123 coupé
The two-door C123 has its own front seats with side controls, and the trim around them is specific to the coupé. The front seat side buttons cover cap is a typical coupé-only part. If you own a C123, look for listings that mention the coupé specifically rather than assuming saloon trim will fit.
Matching colours on an old interior
The W123 was offered in a broad range of interior colours, and forty years of light has changed most of them. A brand-new part in the original colour can look different next to a faded neighbour. Two practical approaches help:
- Replace visible pairs and sets together — both door inserts, all the caps in one area — so the new parts sit next to each other.
- Clean the surrounding trim properly before judging the match. Decades of grime darken plastics more than people expect.
Our guide to caring for classic interior plastics, wood and leather covers cleaning methods that won't make things worse.
Browse W123 parts
Everything we list for the car is in the Mercedes-Benz W123 parts collection. Every part is matched to the original Mercedes-Benz part number and made to order, typically taking 3 to 14 days before dispatch, with worldwide shipping and free delivery on orders over £99.