The transmission in the Mercedes 126 is a very robust design, as one would expect. In its day, it was one of the best units available, which led Porsche to use it in the legendary 928. But as with all other systems on these cars, we should not let the reputation for longevity stop us from performing frequent services.

As a general rule of thumb, transmission fluid should be changed every 30,000 miles. Unlike modern cars, where the trend is to do away with service access ports altogether, these Mercedes transmissions allow us to drain not just the pan but also the torque converter. In other words, we can remove almost the entire fluid charge without resorting to such gimmicks as power flushes.

Whereas engine oil should be changed hot, transmission fluid is best changed when merely warm to protect the mechanic from a very real risk of scalding. » Read more: Mercedes 126 Repair – Transmission Service