Mercedes-AMG A35 W177: hatch or saloon, OPF/GPF or not?
The A35 has the most listings, so start by checking two things: whether your car is the hatch or the saloon, and whether it has a petrol particulate filter (OPF/GPF). Hatchbacks are all listed as OPF/GPF cars, with a cat-back, decat and large-bore sports cat downpipes, a GPF/OPF bypass, Active Valve Control and two sets of replacement tips.
The saloon is listed in both forms. OPF/GPF saloons have a cat-back, decat and large-bore sports cat downpipes, a GPF/OPF bypass and Active Valve Control. Non-OPF/GPF saloons have a cat-back, a front-pipe-back system, a resonator bypass and both sports cat and decat downpipes. The large-bore sports cat downpipes come in two part numbers (SSXMZ135 and SSXMZ151), so compare the fitment options on each listing.
A45 AMG W176 and A45 S W177 exhausts
For the A45 AMG W176 (2012-2018), Milltek lists a cat-back, sports cat and decat downpipes, and HJS Tuning ECE downpipes. The A45 and A45 S W177 hatch (2019-2021) has a particulate filter-back system plus sports cat and decat downpipes. The CLA35 and CLA45 have their own listings in the CLA-Class collection.
Downpipes, de-cats and road use on the A-Class
Sports cat downpipes and the HJS ECE downpipes keep a catalyst in the system. Decat downpipes are for off-road and competition use only and will fail an MOT emissions test, and like most downpipes they need an ECU remap. GPF/OPF bypass pipes and the resonator bypass are louder, motorsport-oriented parts rather than everyday road options. You can see all of these in our downpipes, de-cats and sports cats collection.
Valved, resonated or race: setting up your A35 or A45
Many A-Class systems are offered valved or non-valved, and Milltek's Active Valve Control is listed for the OPF/GPF A35 hatch and saloon. Resonated versions are quieter, with less drone at a motorway cruise, while non-resonated and Race non-resonated options are louder; on some systems the resonated option is marked EC Approved. Some listings also carry fitment options, such as whether a part fits the OE system or a Milltek system, so pick the one that matches what is already on your car.
Buying your A-Class exhaust from Milltek Exhaust Shop
Pop your reg into the lookup at the top of the page to filter the listings to your A35 or A45. Delivery is free in the UK and we ship worldwide, with Klarna and PayPal available. Our workshop in Stoke-on-Trent can fit your Milltek parts.