🔧 Maintenance Schedule Overview
Oil 7,500-10,000 mi BMW LL-01 synthetic. 8HP transmission fluid 60K (despite "lifetime" claim). Spark plugs 60K. Coolant 100K. Brake fluid 24K. Differential oil 60K.
The 3 Series is the benchmark sport sedan. The F30 (2012-2018) and G20 (2019 plus) are both refined drivers. Reliability is acceptable for German luxury but ownership costs are high. Stay with N20 (4-cyl) or B58 (6-cyl) engines.
Ranked by severity. Critical items are red flags that should change your buying decision or pricing. Important items need a documented fix. Good-to-know items are wear items and ownership realities.
4-cyl N20 has a documented timing chain guide failure. Catastrophic engine damage if it lets go. Pre-2016 4-cyl models are risky.
6-cyl 2012-2015 with N55. The OFH gasket leaks onto the belt and starter. $1,500-2,500 to fix correctly.
Modern engines, much better. B58 in particular is one of BMW's best engines ever. Look for service records.
Run-flats cost $300-500 each and ride poorly. Many owners switch to non-RFTs and carry a tire repair kit.
Universal across BMW. Plan for $800-1,200 preventatively.
F30 head unit is dated. G20 introduced iDrive 7 which is far better.
Common $200-400 fix on N20 and N55.
M340i with B58 is the buy. 382 hp, exceptional reliability, refined cabin.
Best and worst years compared. Use this when shopping listings.
Plug an OBD2 scanner in before money changes hands. These are the codes most commonly seen on the 3 Series. Pending codes matter as much as active ones.
Oil 7,500-10,000 mi BMW LL-01 synthetic. 8HP transmission fluid 60K (despite "lifetime" claim). Spark plugs 60K. Coolant 100K. Brake fluid 24K. Differential oil 60K.
$1,200-1,800/year routine. Lifetime non-routine $7,000-12,000 to 150K. Use independent BMW shops, not dealer, to control cost.
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Always run the VIN at NHTSA before purchase. Open recalls are free to repair but must be addressed.
2021 plus G20 M340i with B58. For F30, 2016-2018 with B48 or N55 are safer than earlier N20 cars.
2012-2015 N20 4-cyl without documented timing chain repair. N55 with no OFH service.
Acceptable but expensive. Issues are usually not catastrophic but each repair is large.
200K-250K is achievable on B58. F30 4-cyl typically 150K-180K before significant work.
Yes. One of the best modern inline-sixes. Used in M340i, X3 M40i, Z4 M40i, and Toyota Supra.
Many owners switch to conventional tires and carry a repair kit. Ride and cost both improve significantly.
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