The N57 is the six-cylinder diesel in the 330d, 530d, 730d, X5 40d and the tri-turbo M50d. It is a strong engine and a common replacement. The failures that bring one into our yard are usually the swirl flaps, the EGR cooler, or a bottom end that was asked to live with diluted oil.
Which N57
N57D30A, N57D30B and the tri-turbo N57D30C do not share turbos or manifolds. A single-turbo 530d engine will not run an M50d, and an X5 oil pan will not always fit a saloon. Read the full code, then match the chassis.
Flaps and the manifold
The swirl flaps sit in the inlet manifold. When a spindle breaks, the metal can reach a cylinder. On a used engine, look at the manifold: missing flaps, a blanked port, or a manifold that has been replaced are all facts you want in writing. A blanked manifold can be a careful repair or a botch. The photos should show which.
Cooler, turbo and oil
An EGR cooler that has leaked coolant into the intake leaves a white trail and, in the worst cases, a hydrolocked engine. Ask whether the cooler is still fitted and whether the oil was checked for coolant. The turbo shaft should not have heavy in-and-out play. A little radial play on a used turbo is common. A blade that has touched the housing is not.
If you can, have a compression test done before the old engine is scrap. Even numbers across the six cylinders matter more than one high reading. We do not start pallet engines in the yard. The stamp, the manifold and the drained oil are what we can show you.
Full N57 guide · Another N57D30A listing
Leave the old manifold off if it failed
If the car ate a swirl flap, the replacement engine needs its own manifold or a repaired one, not the broken casting from the floor. The same applies to an EGR cooler that was passing coolant. Bolting the failed parts onto a good N57 recreates the failure that paid for the engine.
Bleed the cooling system slowly. A cooler that looks dry on the pallet can still hide an air pocket, and the first motorway pull is a bad time to find it.
The yard is at Andreas Meyer Straße 38, 22113 Hamburg. Call or WhatsApp +49 15510 030835, or email autowerkeengines@gmail.com, Monday to Friday, 9:00 to 16:00 CET. Shipping is 249 € per order. We are an independent seller, not BMW AG.