Used BMW 1 Series Anti Roll Bar

No — the E87/E81 (2004–2011) and F20/F21 (2011–2019) are completely different generations with different subframe and suspension geometry, so their anti roll bars are not interchangeable. You need to source a bar from the correct generation for your car. Always confirm the exact part against your registration with the breaker.

Yes, it matters significantly — the E87/E81 (2004–2011) and the F20/F21 (2011–2019) use different suspension designs front and rear, so anti roll bars do not cross between these generations. Within a generation, engine size can also influence bar diameter, as heavier or more powerful variants were sometimes fitted with uprated bars. Always give the breaker your full registration so they can match the correct part.

Trim level alone does not determine anti roll bar fitment, so an SE and an M Sport of the same generation are likely to share the same base bar diameter. However, M Sport and later M140i variants may have been fitted with different suspension specifications that could affect bar sizing, and this is not always straightforward to confirm. Route this to the breaker with your registration to make sure you get the right spec.

The F20 ran from 2011 to 2019 with a facelift in 2015, but the underlying suspension geometry was not significantly redesigned at that point, making anti roll bars broadly likely to be compatible across the facelift. That said, small running changes can occur mid-generation, so you should not assume compatibility without checking. Confirm against your registration with the breaker before buying.

The BMW 1 Series across both the E87/E81 and F20/F21 generations is rear-wheel drive and uses independent suspension at both ends, so it is fitted with both a front and a rear anti roll bar. Make sure you tell the breaker which end you need — NS or OS drop links are also separate items if that is what has failed. Quoting your registration will help the breaker supply the correct bar for your axle and engine variant.

Engine size can influence anti roll bar specification, as heavier or higher-output engines — such as the six-cylinder units in the 125i or 135i — may have been paired with different bar diameters compared to smaller four-cylinder variants. This is not always guaranteed but is worth bearing in mind when sourcing a used part. Give the breaker your full registration and engine code so they can verify the correct specification for your car.