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EDIT: Read post: http://ericthecarguy.com/kunena/8-Service-and-Repair-Questions-Answered-Here/41968-86-volvo-740-turbo-vibration-and-noise-issues?start=70#83381
Greetings all the way from Norway!
I have an issue with my 1986 Volvo 740 Turbo Intercooler that I can’t find any solution to. When driving past 60 km/h the car start to vibrate. I have had my car to a couple of different workshops, but none have managed to get it fixed.
Thought I could mention some technical specs about the car.
Engine – B230ET (134kW, turbocharged)
Injection system – Bosch Motronic ML 1.0
Gearbox – M46 (manual 4-speed + electric activated overdrive)
Rear axle – 1031 (torsen differential)Here is a runthrough of what I’ve done so far:
* Replaced every bushing on the car.
* Replaced engine mounts and gearbox mount.
* Replaced bushing and bearing for the driveshaft.
* Replaced the gearbox with one driven approx. 100.000km
* Replaced the differential and had the rear axle at the Volvo dealer to check for slack. Found well within tolerance.
* New tyres and rebalanced them.
* Changed wheel bearings.
* Changed rubber coupling (hardy coupling) between the gearbox and driveshaft.There have been vibrations since I bought the car 10 months ago. It is a common problem that the bushing for the driveshaft goes bad (which causes vibrations), so I didn’t really see that as a problem. After changing it I also realized that the driveshaft had a loose piece inside it that were impossible to remove. I then bought a used driveshaft. The vibrations were now less intensive, but very noticeble. I then replaced much of the things mentioned above, without any luck. Had it at a workshop to get the issue sorted out, the driveshaft were then replaced again with another used one. Got the car back as “fixed”, but there were still vibrations. Turned out the workshop installed it wrong (splines mismatched the balance markings. I corrected that, now the vibrations are almost gone, but are still there. Doesn’t look like any workshop know how to fix a RWD car anymore. None have equipment to measure angles etc.
Any suggestions on what to do here? This have been bugging me for a long time and won’t give up until it is fixed!
– Frank
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I’ve not contacted the workshop that did the “rebuild” of my rear axle. I would guess they’re not that eager to pay for the new axle I bought. They did after all try to convince me that all the noises and vibration is normal in a RWD car. My conclusion is that they don’t want to repair my car, they just don’t care. So much for the “excellent service” provided by dealerships.
I know angles can be a factor to vibration. However, I’ve not lowered or raised my car. It should be stock height as it have new springs. The joints on the drive shaft are probably old. I can feel some very slight slack on the one closest to the rear axle. I’m not sure what the tolerance is, but would guess they need at least a tiny amount to move completely free.
I disconnected the drive shaft yesterday. The sleeve was there, but was much play between it and the pin. It was damaged and missed some pieces as well. The rubber is probably very old and become hard and brittle. That, and the play would most likely create some vibration at given speeds and when load is put on the drive train. I bought a new sleeve, and new joints as well just to be sure.
I did a small garage fix and taped the pin to make it slightly thicker. I think most of the tape got pushed back when I assembled it again, but seemed to help slightly. I can still feel some vibration at the speeds and when I accelerate, but it doesn’t shake as much when I release the clutch after changing to a lower gear.
[URL=http://s1218.photobucket.com/user/frankbilder/media/20131115_121659_zps3e83d14b.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/20131115_121659_zps3e83d14b.jpg[/IMG][/URL]
I would rebuild that entire section. The rubber must play an important
dampening part. Once again great work. Keep us posted on your progress.
This has been a great thread. I know its been a headache for you. 🙁
check on line. Maybe someone has come up with better parts/materials to
replace those parts with.I’ve used better parts where I can. As an example, all the bushings are polyurethane and the motor mounts are a reinforced type. Unfortunately I’ve not found anything for the drive shaft. I think the biggest problem here is the age. That rubber is around 30-ish year old now, so it is to be expected it dissolves to pieces. The u-joints are probably quite old as well. Hopefully the new parts I’ve ordered solves the issue. The sleeve is a so called “classic part”, so it will take a couple of weeks to get it from Sweden.
I didnt know that bad alignment wouldnt cause vibrations. Thanks! Makes sense though, an out of angle alignment would cause “even” uneven wear but not a wobble persay. (Ive never used the word persay, spelled right? Lol) I was thinking tires given the list of replaced parts. Tire pressure, balance etc. Are all four tires the same? I do have a follow up question though in regards to alignment and vibration, wouldnt a bad ball joint or tie rod cause a vibration and also throw off the alignment? Just learning here. Thanks.
[quote=”grg8888″ post=78995]Alignment angles can affect vibration, but mostly only if there are any old u-joints involved. A u-joint transmits rotation smoothly when it’s straight, but with an increasing wobble as the angle increases. The wobble is a combination of increased rotational speed, lowered rotational torque, and a sideways torque too, varying at twice the driveshaft speed. You can model this with a u-joint extender on your wrench.[/quote]
Alignment angles do NOT cause vibrations. What you speak of here is a ride hight issue, not an alignment angle. That said, the issue you describe is with a U joint, once again, not related to alignment angles, ride height yes, but not alignment angles. Yes, extreme driveline angles can cause issues but these are not what I would refer to as traditional alignment angles like toe, camber, and caster.
Driveline issues are very difficult to track down. It sounds like you’ve tracked down yours, well done. You may need to replace the old rubber parts to fully get rid of the issue. At least now you know where to look. Thanks for keeping us up to date. Let us know if you make anymore progress.
Yeah, I was thinking of “alignment” as in the general sense of the alignment of the driveshaft. Not as “alignment” in the sense of toe-in, caster, camber and the like.
[quote=”bbryan1″ post=79220]I didnt know that bad alignment wouldnt cause vibrations. Thanks! Makes sense though, an out of angle alignment would cause “even” uneven wear but not a wobble persay. (Ive never used the word persay, spelled right? Lol) I was thinking tires given the list of replaced parts. Tire pressure, balance etc. Are all four tires the same? I do have a follow up question though in regards to alignment and vibration, wouldnt a bad ball joint or tie rod cause a vibration and also throw off the alignment? Just learning here. Thanks.[/quote]
Alignment angles do not traditionally cause vibrations. It’s only extreme cases that would cause that and you would also likely need some other contributing factor such as loose suspension parts. I write about this extensively in this article. What is referred to above has to do with driveline angles NOT alignment angles.
http://www.ericthecarguy.com/faq/determining-the-causes-of-vehicle-vibrations
On Friday I used a few hours with the help from a friend to replace the u-joints and the rubber sleeve for the stabilizing pin from the gearbox into the drive shaft. I’ll throw in a few pictures of the new parts below. Before changing the parts I could feel a very small amount of play in the rear u-joint. After changing everything the result is still the same. How disappointing! It still vibrates at the given speeds, and still have a loud noise along with the speeds. The noise only occur if I put load to the drive train, when I accelerate of let go of the pedal. People who sit in the back seat can’t hear what I say in the front seat. Yesterday I were told it sounded like a propeller plane taking off. Others have said thins earlier like “don’t need a subwoofer in this car” etc. I’m quite puzzled about this issue… Now I’ve replaced every possible part that could cause this and a little more than that. Guess it is time to take the car to another mechanic shop and have it looked over again. If I can find someone that know how to repair old rear wheel driven cars without possibilities to connecting it to a computer.
New sleeve and the old one tapped out by welding a small plate to it.
[URL=http://s1218.photobucket.com/user/frankbilder/media/20131213_205122_zpsefcf200c.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/20131213_205122_zpsefcf200c.jpg[/IMG][/URL]
[URL=http://s1218.photobucket.com/user/frankbilder/media/20131213_205310_zpsfdc3595d.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/20131213_205310_zpsfdc3595d.jpg[/IMG][/URL]And the new u-joints in the middle and rear end.
[URL=http://s1218.photobucket.com/user/frankbilder/media/20131213_224503_zps8bb96498.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/20131213_224503_zps8bb96498.jpg[/IMG][/URL]
[URL=http://s1218.photobucket.com/user/frankbilder/media/20131213_224515_zps687c012c.jpg.html][IMG]http://i1218.photobucket.com/albums/dd414/frankbilder/20131213_224515_zps687c012c.jpg[/IMG][/URL]Not directly. When I had it at the dealership they bought in a new drive shaft as it were cheaper than having my old one rebalanced. They claim that they tried the car with the new one and that the result was the same. So they put on the old one again and sent the new one back. I don’t trust what they say as they also said they checked the differential in the old axle and found it good. I could see that the cover wasn’t even taken off as the rust protective coating wasn’t disturbed.
I have also tried two other used drive shafts as well without luck. The first one was on the car when I bought it and had a loose metal piece inside, causing vibration depending on the position of the piece inside the tube. The second one turned out to be two different drive shafts (they can be separated in the middle) and put together as one piece. The third is the one I use now and is the one the dealership took off and claim they tested the car with a new one before putting it back on again. I can also mention that the dealership didn’t put it back correctly either, the balance marking were off and I had to pull it off and put it back together correctly.
I’m going to bring my car to another shop on Monday that specializes in tuning cars, they should have better knowledge about this than the dealership.
Had the car in to get the front brakes fixed and have it technically inspected as is mandatory by the European Union every second year. Passed without marks, so good to go for another two years now. While I had it in I asked the mechanic to look at the vibration issue. He did not do any troubleshooting, just looked quick at it. He suspects that the drive shaft is installed incorrectly. The alignment marks he claimed look more like marks left by tools, just a coincidence that one of the marks look like an arrow. I’m going to hand in the car again at a later date when they have time to get everything checked more thoroughly. Having the drive shaft rebalanced would cost about $1000, so hope they find another fault that is cheaper to fix.
Perhaps, but I’ve bought one earlier, and might get a bad one again. People can’t be trusted when it comes to used parts. I also think that the dealership were lying about the price to have the shaft balanced. The other workshop I spoke with said it should cost around 2000 NOK, which is roughly $300. Might as well get it balanced, as buying used parts over and over quickly cost about the same. A used one cost about $100.
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