What causes the vacuum pump on a 240D 77 to self destruct? This has happened to my 240D four speed manual at least four times in the past 20 years.
Fortunately in all cases it happened at very slow speeds and I managed to somehow stop the car safely, any thought as to how to survive this if it happens at freeway speeds?

Vahe
240D 77

Lack of lubrication? In some Mercedes diesels there have been gasket changes over the years including a "pocket" style designed to trap some oil so the vacuum pump has lubrication when the engine first starts. That might not apply to your engine but it's all I can think of beyond a statistically-unlikely run of bad luck.

One question -- where are you getting the replacement vacuum pumps?

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

The car is in the shop, supposed to get it back today, I do not beleive that they cut corners when it comes to the parts as they always chargs an arm & a leg for any work on this car.

Vahe