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Discussion Starter · #1 ·
I'm posting this for my little brother.
He has an 85 300D Turbo, mileage unknown. Purchased for $1000 USD.
Under heavy throttle, we start to hear a high pitched whine right before the tranny shifts (automatic) and then it stops after the shift. Seems to happen between first and second for the most. Doesn't happen when accelerating lazily. Any ideas?
Also the car is generally a pig. My dad's identical 85 is much, much faster. Just needs a tune up, or some other lurking problem?
 

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1981 300D
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davemsmith said:
I'm posting this for my little brother.
He has an 85 300D Turbo, mileage unknown. Purchased for $1000 USD.
Under heavy throttle, we start to hear a high pitched whine right before the tranny shifts (automatic) and then it stops after the shift. Seems to happen between first and second for the most. Doesn't happen when accelerating lazily. Any ideas?
Also the car is generally a pig. My dad's identical 85 is much, much faster. Just needs a tune up, or some other lurking problem?
Sounds like the turbocharger to me. It with mostly happen when the accelerator is floored or near floored. As the engine speed picks up, the turbo will kick inm, sucking alot more air into the engine, the turbine will be spinning I at speeds of 150,000 rpms a minute, so....its a sound that is supposed to be present.

it should be coming from the passenger side in the engine bay.
 

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Discussion Starter · #3 ·
No, it definitely is not the turbo. Too loud, and it's the wrong pitch. Lower than a turbo charger. Plus my dad's turbo is very, very quiet.
 

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'77 6.9, 74 240D, 96 Ram 5.9L Cummins
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It just may be time for a transmission rebuild and or the bands for 1-2 are going out.
 

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W-1-2-3 Go!
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Check that the U or J shaped tube from the air cleaner to the turbocharger housing did not fall off. This happened to me and I heard a whine. Reinstalled it back and no more whine.
 

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