Hi, I have a volvo 240 wagon (5spd manual) with over 300k miles on it, bough it back in December of 2013, and it's been a great car, very reliable, but has a super annoying vibration between 40 and 60mph, but it mostly goes away by 65-70+, you can still see the rear view mirror vibrating, so it's still there, but it kinda mellows out a bit to where it's bearable.
I put some good used tires on it when I got it, thinking that the old dry-rotted Michelins were causing the vibration(which, come to think of it wouldn't be much of a speed specific problem if it had been the tires...duh), had the tires balanced again and rotated once it didn't change anything, still the same.
The vibration is not RPM related at all, cause it's the exact same when the clutch is pushed in and idling, still at said speed.
It also vibrates on deceleration from 45 down to 30 or so.

I have put probably 6k miles(mostly in town) on it since I got it, and it hasn't gotten any worse, back in April I drove about 1500 miles on the hwy where it wasn't vibrating so bad, and nothing got worse.
Yesterday I took the rear driveshaft off to check the u-joints but they seem totally fine. so while it was off I started it up and put it in gear and sure enough I feel the vibration roughly around the speed I feel it when it's driving, so Im thinking it's the center support bearing.... not sure tho. There is some play when I grab the driveshaft by the center support and move it back and forth, but the rubber mount thingy looks to be in good shape. I think I can hear a slight ticking noise coming from that bearing when I spin the drive shaft with it out of gear, not a continual ticking, but a slight tick when I start it moving, then it's quiet. I'm guessing I shouldn't hear anything from it?

Bottom line is that I think it needs to be replaced, but my delima is that I might have a problem getting the bearing in time to fix it before I go on a 500 mile(total) trip this coming weekend.... Am I gonna be in danger of something coming apart and leaving me stranded If I can't get it fixed and end up driving another 8 hours on the hwy? I drove for some 20 hours before and nothing changed... but will I be messing up something else by continuing driving it like it is?

I'm also kinda wondering what it could be if it still has the same problem after fixing that bearing... (>_>)

I would appreciate any feedback, thanks, Jesse

 

Generally when the center support bearing goes bad the symptoms are a high-pitched whining noise that is speed-dependent and does not go away when the car is in neutral. When you have this vibration, does it go away if you drop it into neutral? If the vibration goes away at those speeds with the car in neutral, then I would suspect engine mounts or even the exhaust system. Check the mounts to see if they are bulging or torn. For the exhaust, go under and wiggle it around to see if it is contacting the body anywhere. Any place it touches will transmit vibrations to the car. It should be completely isolated by the rubber hangers.

 

It stays the same when put into neutral, basically if the car is going that speed, it is vibrating, whether it's in neutral or in gear, one time I even turned the motor off and coasted while going 60, vibration doesn't change any.

 

I'd say you are on the right track looking at that driveshaft and assoc. parts... I'd have looked at tires first but looks like that was eliminated so the driveline would be next.

 

+1 on lev's response. Since vibration is still there in neutral, then check out the drive train. On the drive shaft, make sure the front and rear shafts are aligned properly. Also, check your rims to see if any are bent (although if any were bent bad the shop that balanced the tires should have told you).

 

I had the exact same issues on my 244. Check that the tire walls do not have any undulations on them.

You can also try swapping front and rear tires. And as act and lev pointed out, check the rims too.

I had undulations on my front tires that caused vibration in the same speed zone you mention. I swapped it to the back and it slowly got worse there also - after which I got new rubber on all 4s.

 

Thanks! I'm gonna try to get the bearing swapped out this afternoon after work, but if I can't get the bearing before this trip, is it something dangerous enough that I shouldn't drive it on the hwy?

 

Is your wheel bearing worn out to require replacement? Did you grab the wheels feel for any side to side or up down movement?

Also, my drive shaft has the similar slight play in the middle but bushings seem to be decent.

I still think you should check the tire walls.

 

A few weeks ago I swapped the tires front to back, and the vibration stayed in the same place, I feels kinda central, can't really feel it in any specific direction. The guy at the tire shop said the rims were straight and although there is some wear on the inside of 2 of the tires(that wear was there when I got them, so it's not from this car), he said that he couldn't find anything on the tires that could cause any kind of vibration like that

 

Not sure on the wheel bearings, but I would think they would get worse after putting 6k miles on them, I've been driving it for 6 months with no change in symptoms

 

Does it worsen when you brake in within those speeds? So let's say at 50 mph you hit the brakes (normal braking not gentle and not emergency braking) - does it worsen the shake?

In my case, I could feel it vibrate worse till about 35mph after which it would become stable/smooth.

 

It kinda does vibrate a little more when I hit the brakes then, but yeah, under 35 or so nothing at all.
Now I know that it needs brake work, cause I feel what I think is a warped rotor when I'm braking from 25 down to 0, but not really a vibration, just feels like the car goes up and down a tiny bit, then as soon as I let off the brakes then stops

 

Actually tho, I've basically eliminated all tire/rim/wheel bearing/brake problems by putting it in gear with rear driveshaft disconnected and getting the same vibration

 

Where did you disconnect the driveshaft? at the axel? My first thought was (If rubber and tires are good) that center bearing. Mine is going bad, and making the noises mentioned by someone else... but my brother had a center bearing go bad on his 700 series car, with no noise, just vibration under load. Maybe I missed it, but did you inspect your engine & tranny mounts? these go bad often...

 

I disconnected it at the back axel and pulled it all the way off.
Mine doesn't make any noise that I know of while driving, just the vibration. I haven't really checked the motor or tranny mounts, but if it was a motor mount I would think it would change with the rpms. Once while driving it at 60 I put it in neutral and turned the engine off and coasted....nothing even made the slightest change in vibration, that's what made me think it wasn't motor mount. Don't know about the tranny mount, but I read somewhere that if the tranny mount was bad that it would make the flex plate(between the tranny and driveshaft) go bad soon after, my flex plate looks like it should I think.

 

Hum.... more questions then. Does it vibrate in all gears? Or just OD? Wait... '92, scratch that... does it vibrate in all gears or just 5th? Could still be a mount, but I'm thinking there is a transmission issue. The tyranny mount is easy to check--it is right there under the transmission.

If the vibration happens only in one gear (5th), i'm thinking there is an internal issue, in which case, I have no real experience.

 

Every gear, well any gear it's in going that speed.

 

Ok, just got the center support bearing(finally found somebody in town that had it :O ), gonna "attempt" to put it in now, will post later with results

 

the rubber donut the bearing rides in goes bad too.

when the transmission mount is bad, the drive shaft is out of alignment, this also can cause speed-dependent vibrations.

if you have to separate the halves of the drive shaft, do be sure to mark how they are lined up, so you put them back together in the exact same place, the whole assembly is balanced that way, and the U joints have to be phased properly.

 

Ok, thanks for the input. I will make sure I do that, I didn't mark it before I took the back driveshaft off the other day, so I wonder if I can find out how to put it back in right (>_<)

I haven't taken it off yet this time to work on the bearing, I started to but I looked at the bearing and it's the wrong one. Without taking mine off and measuring the bearing, just my looking at it it looks like mine is about 2" for the inside of the bearing. So I bought the wrong bearing, I got one from O'Reillys that is 1.38" ID(35mm), now I see that there is also one with 1.77" ID(45mm)....I'm very confused, cause I also see that some have a 50.8mm ID, which is what mine appears to be. Does any body know where to get that bearing? (The 2"/50.8mm one)
I found it online but the numbers on the bearing they pictured was the 1.77" ID...