My '85 300D's engine makes a squeeling sound under load over 2000RPM. I removed the air filter housing and air intake tubing from turbo and rev the engine, on deceleration, you can hear a brief squeal. With the engine off, if I try to spin the turbo with my finger, it is hard to move, I would expect it to spin freely. Does this sound like the turbo bearing has bound up?

I would say your tubo is toast...or close. You should be smoking like crazy if the turbo is not working.

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1983 300SD 343K everyday car
1983 300SD 285K from junk yard-tooks parts from deer car- runs great. Brothers car.
1984 300SD parts car-Hit deer
1979 300D 175K non-turbo "Doctor"
1979 300d parts car

I agree that turbo should spin with extremely little effort from your finger.

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1971 280SE W108
1979 300SD W116
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1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

Park the car and get it towed to a shop asap. I would NOT drive it like that.

I don't know how extreme the wear is on your bearings in your case, but if it were to break oil could get into your intake (possible runaway ) or in the exhaust (LOTS of smoke and LOTS of p*ssed off people behind you.)

If you can remove it yourself and take it in for rebuild/exchange you could save gobs of money and downtime. You could also save much more if you can rebuild it yourself.

I recently had the same thing happen. I found the intake and exhaust bolts were loose. Tightened everything up and everything is back to normal. So before spending any money I would check the bolts.
Just my $0.02 worth.

Squeal or whistle is a leak on the pressure (intake) side, occasionally exhaust.

Check for leaks first.

The turbo wheel will not spin, it stops almost instantly if you push it around on most diesel turbos. Gas turbos spin a bit more freely, but none really "freewheel" very long because of the oil seals. However, you should be able to turn it with a fingertip. A barely perceptible amount of side play is OK, axial (in and out) play means bad bearings. So do any "tight" spots in rotation. If you have to push much, the bearings are shot.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

because I want to follow this thread.
Curious about resolution.

Jerry, please keep us current on your situation.

Thank you.

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