BMW offers some of the most refined driving experiences out of any other brand. Steering is tight, manual gearboxes are solid, and the engines climb revs with boisterous confidence. Like most high-end German cars, BMWs have overbuilt engines and drivetrains, which makes them robust machines. Some things break like air conditioning and electric seat adjusters, however, the engines and drivetrains generally hold up well even to severe abuse. Here are some of the most reliable BMWs ever made.
Naturally aspirated simplicity: 325i
The BMW 325i and 328i from 2006-2011 are widely considered to be the most reliable BMWs ever made. They used non-turbocharged engines called the N52, which was an inline-six that used electronic throttle control and variable valve timing. It used a block composed of magnesium and aluminum and redlined at 7,000 RPM. As the last naturally aspirated inline-six from BMW, the N52 made 228 horsepower in the 328i, and 215 horsepower in the 325i.
These engines weren’t without fault. They faced cooling issues and starter problems, but because of their simplicity, they avoided more complex issues. Its successor, the N54, went through nine different iterations of its high-pressure fuel pump, before settling on a design that worked. Simplicity keeps a reliable BMW preserved.
E34 BMW: the nimble 5-series
The E34 BMW was built like a tank. It took a lot of abuse and kept running. It used several engines, and the M30B35 stands out as a well-balanced inline-six with 208 horsepower, according to MotorTrend. The M30B35 used an iron block with an aluminum head and spun its camshaft with a chain. Its rotating assembly operated with a forged steel crankshaft. The M30 was BMW’s longest-produced engine at 27 years.
The car was nimble, fun to drive, and used a bulletproof transmission as well. Horsepower scooted the car along at a reasonable rate, despite its hefty curb weight. The car romped around mountain passes with relative ease and cultivated grip. Its ride height meant it could handle some off-roading as well, provided the traction was there. The E34 was a prime example of a reliable BMW.
E46 or E90 diesel: powerful and reliable
The 335d stands out as having a terrifically powerful and reliable engine. It used the M57D30TU2, a turbocharged inline-six diesel engine producing 280 horsepower and 430 lb-ft of torque. In earlier years, between 1999-2001, the 330d had 181 horsepower and 287 lb-ft of torque. The car weighs a bit more than its gasoline-powered variant, but the engine is solid. Its second iteration used an aluminum block.
The 320d is another diesel option, however, it has many problems. Aside from having only four cylinders, many owners report having to prematurely replace the timing chain. Nevertheless, the engine should last several lifetimes with proper maintenance, including clockwork oil changes and keeping an eye on the gear oil.
In spite of finicky electrical systems, BMW engines and transmissions offer an experience like no other. BMW might make the list for least reliable cars, but its engines stand the test of time, and the cars offer superb handling and acceleration. Fixing things can be expensive on BMWs, however, as long as routine maintenance is performed, they last forever.