diagnosis of transmission problem--300SD

I have an '82 300SD with about 90,000 miles. The transmission sometimes slips between gears with a slight rpm surge. Also, when I put it in gear (especially into reverse) I sometimes get a 3-7 sec. delay before gear
engages. When I shift manually, it is fine. Transmission fluid is good and at appropriate level.
Does this sound like a vacuum pump issue or a bad transmission? Or something else? Thanks in advance, Joel
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You need to do a tranny filter and fluid change first. Filter is the issue... if it is clogged due to age, it will deprive your tranny of pressure.
I would also simply drain the fluid two more times after the first... give it 35 miles or so between each drain to fully flush out as much of old tranny fluids.
Then we'll diagnost the problem again...
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Thanks. I have an '83 300SD with the same symptoms, although I have around 340,000 miles on the clock. I will do that tranny thing very soon. Thanks again for the tip.
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Is that original tranny? I never heard of so long... usually about 250000 miles range max.
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Oh, yes. This car has had no majors. I fully expect to get a half million miles. You do know that the Mercedes is in the Guinness Book of World records as the worlds most durable car? There is a 1933 Benz with over six or eight million miles--with no majors. Hard to believe, but there it is.
But, as for 250,000 max? Nah. Maybe a gas engine, but not a diesel. The last two diesels I bought had well over a hundred thou on the clock--still babies.
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I know of very little gas engine MB last past 180,000 miles... Only the diesel last past 250K miles... but majority highway driving.
The million miles automatic MB has changed tranny... just not the engine. unless it is manual... then they will last quite a while but still need clutch job.
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When was its fluid and filter last changed? S/B done every 30 - 35K miles.
For future reference, the symptom you describe is known as "flaring."
This box s/b good for another 100+K miles so take care of it.
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