Hi, I'm new here and a fairly new Volvo 240 owner. I have a question about my old and very worn Volvo 240. My 240 is a 1987 with a 5 speed manual transmission that is making a vibration and noise when I take my foot off the gas pedal. It sounds like a bearing but does not do it when I accelerate. It also makes the noise when up-shifting for a brief moment before acceleration begins. At first I thought it was a bad motor mount because it also seems to wobble the shifter and rumble a bit when I am in reverse. I also considered the possibility that it could be a driveshaft issue until I realized that it was making the noise when I shifted up to a higher gear momentarily while my foot is still on the clutch. Am I looking at a bad transmission here? Any thoughts as to what to look at first? I only paid $500 for the car but I like it and I would hate to have to get rid of it after only a the few months I have had it. Thanks.

 

Check you u-joints. Specifically the rear-most one just before the differential. From my experience on a couple of 240s when the rear-most u-joint drys out and seizes you tend to get vibration when decelerating. On my daughter's 240 it was really violent (she thought it was a problem with her brakes). You could drive the car at 70 and experience no vibration but decelerating at 20 mph caused severe vibration.

Disconnect the rear of the driveshaft from the differential and check the u-joint there to see if it flexes easily. Any binding indicates it needs replacing. If it is bad, you probably should drop the whole driveshaft and check the others. While it is off check the center support bearing as well.

 

act1292, I did initially consider that as a possibility but since it makes the noise when I up-shift with the clutch still depressed I thought it was unlikely. I will still take your advise and check that. Thanks for your reply.

 

I've seen three issues on older 240s that can cause this. The first is the center support bearing on the driveshaft. The second is the bushing in the tailshaft of the transmission. We used to change a lot of those. The third is the flex joint.

https://www.rockauto.com/en/moreinfo...287637&jsn=413
https://www.rockauto.com/en/moreinfo...287637&jsn=422
https://www.ebay.com/itm/NEW-Propart...QAAOSwTgdbLWEM

 

Tony1963 notes other possible culprits for this. For the center support, inspect the rubber there and see if it is all intact with no tears or cracks. Usually when the bearing goes bad it whines - usually in cold weather. The whine wouldn't change as you disengage the clutch. For the tailshaft bushing, when it is worn you usually start to get leaks out the rear seal of the transmission. All easy things to check.

 

jim914. You have to get this car on a lift and examine the whole driveline. The way you describe it it could be anything. Once the drive line is looked at and sorted, then the tranny...



BTW, is it a M46 OD (button on top of shifter) or a M47 (true 5 speed)?
How many miles?

 

I think it's a M47. I found a bit of a mess at the back of the transmission. There is a rubber part that is destroyed where the driveshaft meets the transmission, I'm not sure what this part is called. What is this part called?

 

Its commonly called a "flex joint" and used by European car makers. It is one of the three failures that I mentioned earlier.

https://www.rockauto.com/en/moreinfo...287637&jsn=422

That needs changed YESTERDAY. Very unsafe.

 

Thanks, fortunately it's not my only vehicle so it's off the road until this is fixed anyway. I'll order the part from ipdusa.com this week and hope that it's the only issue. The rest of the drive shaft parts seem OK.

 

Flexdisk aka Giubo (after the company that first made them). they should be inspected every few years and if the cracks get bad, replaced. Volvo only used them on the manuals, Mercedes of the same era used them on all cars, and there were two, one in front, one in back.

I hope the ends aren't messed up, when they implode like that, they can damage the driveshaft and/or transmission output shaft ends.


this is about as bad as I'd let them get, we pulled this one out of my wife's 1994 Mercedes E320 wagon shortly after buying it...

 

These things can typically go about 20 years. What appears to do them in is that the rubber begins to dry out, crack, then fall apart. It is what you see with suspension bushings over time, the same type of deterioration.

As a rule, if they are 20, make them go away and replace.

 

if that part fails at speed bad things happen. common failure on mercedes.

 

only if they are neglected... any good mercedes mechanic would be inspecting those annually as part of a overall service, along with checking the suspension bushings, differential mounts, and all the other similar sorts of bits.

 

yes a mechanic having the car on a lift would check those flex discs, but there have been horror stories especially regarding older MB diesels having original discs failing at speed creating major havoc ...
i had a W123 for many years so i checked them regularly.