Just recently I noticed that when I am driving there is a heavy loud vibration from under the car. It almost feels like its coming from the rear. Its a steady pulsating vibration that gets slower and slower in intervals the faster I drive. When I'm doing around 70-80 on the highway its a constand vibration for about 5 seconds and then goes away. Back and forth. As I accelerate the vibration is quicker. I can't really think of any other way to describe it.

Have a look at the centre propshaft bearing - if the rubber support is knackered then it could be flipping about a bit too much.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

X2
That is how it feels when it needs replacing.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I just replaced this in an 85 300sd along with flex discs and now I have this problem and didn't before.

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... um, did you align the shaft sections like they were before?

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I don't mean to hijack this thread. But yes I marked everything that came apart and it went together the same way.

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Assuming everything is tight and in the correct place:-

Unfortunately sometimes it is possible that you fix one bit that moves too much and you then need to fix another bit... vibration will often "show" at the weakest link

Check out your exhaust mounts but most importantly the other engine mounts...

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Exhaust is fairly new so mounts are still tight. Motor mounts are good too. Tranny mount is a little soft but is still in tact. This is a driveshaft (spinning) resonance.

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It`s been mentioned here before, to place 2 hose clamps on the driveline oposite to each other. drive the car and then move them around till you find the smooth spot. kind of a crude way to do it, but might work. or take the DL to a shop that works on them to have it spin balanced.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

A buddy of my dads who's been working on these cars for decades says that according to my symptoms the transmission mount is probably weak. A combination of soft tranny mount and stiff flexdiscs is probably causing this. I guess i'll have to get one ordered.

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Let us know how you get on.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

OK back to the original issue. I have figured out that the rear is bad. Any idea where I can get a center unit from so I can just swap them out?

Not sure what you mean - are you talking about the centre bearing? If so they aren't too expensive new in my opinion. I wouldn't bother fitting a second hand centre bearing.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I'm referring to the center of the rear axle...the pumkin. I don't know what part of it is bad and don't have the knowledge to tear it apart. I figure the easiest thing is just to completely remove and replace it.

The differential should be easy to come by, though someone with more knowledge on them can tell which years have the correct gear ratios for your car.

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