Free Buyer’s Guide

2015 BMW 320i

A simple guide for buyers with no car knowledge. Do most of the work from home, on the phone. Only go and see the car if you like what you hear. The decision is always yours.

The free guide is below. The full guide is made for this car after you pay.

Which 2015 320i is it?

A facelift came in mid-2015. One non-Australian page lists a facelift 320i with 184 hp and 290 Nm. Another says some regions later got a B48B20O0 engine. We could not confirm this for Australian cars. We also could not confirm any all-wheel-drive 320i sold in Australia. Check the engine code and the compliance plate on the car.

Ask the seller: "Which engine code is on the car, and which gearbox does it have?"

Safety rating

• BMW 3 Series, build dates 2012 to Feb 2019. ANCAP says the rating applies to the 320d diesel variant. We found no separate ANCAP rating for the 320i petrol.5 stars (36.76 out of 37)

As published by ANCAP. Older ratings, tested to easier standards than today’s.

The big-money items

You can’t see inside these parts, but you can ask about them.

• Timing chain, guides and tensioner N20 B20 PETROL ENGINE (320I AND 328I). CHAIN FAILURE REPORTS ALSO EXIST FOR N47 DIESELS BUILT UNTIL 2015 (320D).

  $$$ (over $2,000)

  A chain at the front of the engine keeps the valves in step. Plastic guides hold it tight. If it slips, engine parts can hit each other. Australian price not found. The tier is our estimate.

  Ask: "Is there an invoice for the timing chain and guides, and did you hear any rattle on a cold start?"

• High-pressure fuel pump N20 B20 ENGINE (320I AND 328I)

  $$ ($500 to $2,000)

  The pump that pushes fuel into the engine. One page calls it a known fault on some production batches. Australian price not found.

  Ask: "Has the fuel pump ever been replaced, and has the car had hard starting or rough idling?"

• Water pump and thermostat N20 B20 ENGINE (320I AND 328I)

  $$ ($500 to $2,000)

  The water pump moves coolant around the engine. The thermostat is a valve that controls engine heat. Pages name both as weak points. Australian price not found.

  Ask: "Has the water pump or thermostat been replaced, and is there an invoice?"

• Oil leaks: valve cover and oil filter housing N20 B20 ENGINE (320I AND 328I)

  $$ ($500 to $2,000)

  Seals on the top cover or the oil filter holder can leak oil. One page says these repairs cost less than the timing chain. The tier is our estimate.

  Ask: "Have any oil or coolant leaks been fixed, and is there an invoice?"

• Automatic gearbox leaks and fluid service ZF 8-SPEED AUTOMATIC (320I, 328I AND 320D)

  $$ ($500 to $2,000)

  One guide calls this gearbox very reliable. It lists leak points at the oil cooler joins and a gearbox seal. BMW calls the fluid lifetime, but ZF suggests changes. Australian price not found.

  Ask: "When was the automatic gearbox fluid last changed, and is there an invoice?"

Regular maintenance

Look for these on the service invoices.

• Engine oil

  Fresh oil keeps the engine parts moving smoothly.

  As shown in the logbook

• Spark plugs or fuel filter

  Petrol engines have spark plugs. Diesel engines have a fuel filter.

  As shown in the logbook

• Brake fluid

  The fluid that makes the brakes work. It absorbs water over time.

  Every 2 years (our guide)

• Coolant

  The liquid that stops the engine getting too hot.

  As shown in the logbook

• Gearbox oil

  Oil inside the automatic gearbox. BMW calls it lifetime, so ask when it was last changed.

  As shown in the logbook

• Air filter

  Cleans the air going into the engine.

  As shown in the logbook

• Tyres

  Old rubber hardens, even when the tread looks good.

  Replace at 6 years old, even with good tread (our guide). Alignment every 10,000 to 15,000 km (our guide)

• Battery

  Starts the engine and runs the electrics.

  Most last about 3 to 5 years

Questions to ask on this 320i

These are for this model. The full list of questions, with tick boxes, is in the PDF.

• Which engine code is on the car, and what does the compliance plate say about the drive type?

  Good answer: The plate and paperwork match the advert. The seller can read both out.

  Why: We could not confirm an all-wheel-drive 320i sold in Australia.

• Is there an invoice for the timing chain and guides?

  Good answer: A dated invoice with the kilometres, or a clear answer that it has not been done.

  Why: The chain is a known thing to check on this engine.

• When was the automatic gearbox fluid last changed?

  Good answer: A logbook stamp or invoice with the date and kilometres.

  Why: BMW calls the fluid lifetime, but ZF suggests changing it.

Words you might see on an invoice

Timing chain, guide rail, tensioner

The chain that keeps the engine's valves in step, and the plastic parts that hold it tight.

VANOS

BMW's name for its variable valve timing system. It changes when the valves open.

Valve cover gasket or oil filter housing gasket

A gasket is a seal. These seal the top engine cover and the oil filter holder. Both can leak oil.

HPFP

The high-pressure fuel pump. It pushes fuel into the engine.

Mechatronic sleeve

A seal where the gearbox's electronics enter it.

Steptronic

BMW's name for its automatic gearbox.

Two quick checks at home

All you need is the VIN.

• Recalls: recall.bmw.com.au
• Recalls: vehiclerecalls.gov.au
• Money owing: ppsr.gov.au (small fee; check again on the day you pay)

• A $2 PPSR search shows if the car is recorded as free from debt.
• It may also show if the car is recorded as stolen or written off.
• It does not show the amount owing, owner history, kilometres or fines.
• Written-off and stolen data are not always up to date.
• Recalls go by VIN, so ask the seller for the VIN and run the check.

Good to know

• Wikipedia says a class action was filed in 2017 by owners against BMW over faulty units. It does not say which country, and we found none for Australia.

General information only, not an inspection of any vehicle. “Our guide” means our recommendation, not a legal rule. Costs are a rough guide. Information current at October 2026: always check the VIN yourself.