In my auto '89 244, I get a serious momentary vibration when I accelerate hard (or at least as hard as an N/A B230 will). At first it only happened just when the tranny was shifting from first to second, but now it will do it when moving from a stop if I really step on it. I can pretty much completely avoid this by being gentle with the throttle, at least for now.

It has the feel of a shaft rubbing against something because the geometry of the driveline has changed because of the revving or acceleration, but that is just a guess.

Anybody got any ideas of where to look first and what diagnostics I can do ?
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Andy in St. Paul, '91 745 Regina 198K mi, '89 244 141K, '87 245 RIP

My '79 245 had a vibration that was caused by the "U" joints being dry and rusted. The roller bearings were not rolling anymore.
I replaced the center support bearing but the problem didn't go away until I replaced the u joints.
It would vibrate at the same SPEED reguardless of the the RPM's.
It almost felt like it was in the front end at first.

1. Center support mount and bearing. First, I would check to see if the rubber mount is deteriorating.

2. More likely it is tranny or engine mounts. Have you replaced any of these?

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Jim 90 244DL 243K

Motor and tranny mounts replaced about 6 months ago. Problem developed since then, but not immediately afterwards.

Thanks
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Andy in St. Paul, '91 745 Regina 198K mi, '89 244 141K, '87 245 RIP

IMO - I would take a good look at the CSB rubber mount first.

As Kyle245 suggested, a seized u-joint might cause your problem, but normally they clunk with certain loads when they go bad.

A couple of long shots:
1. How is your tranny tailshaft bushing/seal? If the bushing is really loose it might cause a vibration.
2. Is you driveshaft properly aligned? Ever shimmed it?


Good luck,
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Jim 90 244DL 243K

I agree that motion of the tranny would happen when revving and at gear shift time, but I don't see how the new tranny mount install could be bad.

I had my tailshaft bushing and seal replaced not too long before this vibration started. If I had enough play to cause this, wouldn't I also be leaking fluid again ?

Sounded like a bad u-joint would give me vibration all the time rather than just under load and only at gear shift time. is there any diagnostic for the u-joints ?
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Andy in St. Paul, '91 745 Regina 198K mi, '89 244 141K, '87 245 RIP

I didn't suggest that the tranny mount install might be bad, just wondered if it and the engine mounts had been replaced yet.

I'm no expert but....
IMO - Based on what has been replaced, sounds like we've narrowed it down to either the CSB or a u-joint. Test u-joint per Art's suggestion.

CSB - 1. Do a visual test for deteriorated rubber mount. 2. Grab the driveshaft, shake hard near the CSB and see if it moves excessively....

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Jim 90 244DL 243K

Holding out, eh? I was about to pin it on the tailshaft bushing, but you've already been there. Nevertheless, give it a good shake when you're under there again; they leak when the clearance gets bad and the seal gets stiff. U-joint more likely and not ruled out by lack of symptoms when coasting. With one rear wheel up, in park, rotate wheel back and forth watching the rearmost u-joint closely. When you see one half move before the other...

Or just give them a firm grasp and wiggle.