Bad vibration on highway speed

[Syy0628 13]

Hi all,

I am new to the forum and I just got a E36 316i auto.

my e36 316i auto has a bad vibration(bad enough for the interior to shake) coming from the rear of the car above 70kph, and it is speed related, it eases off when let off the gas, and get worse when accelerating or going uphill. Downshift to 3rd does not change the vibration. The car also jerks hard when shifting from N to D or to R. 

Since the vibration is speed and on/off throttle related, I suspect the vibration is caused by the driveline behind the transmission. The Tyres have been balanced, there is no crack on the flex disc, and when I turn the drive shaft by hand, there is no obvious play in the U-Joints, and there is no dent or bent on the rear CV shaft, the bushing on the rear control arm seems to be Ok, and the car drives straight and handles well when cornered hard.

What could be the problem?

 

Thanks 

Edited July 5, 2017 by Syy0628
typo

[hotwire 352]

Are you sure you don't have a seized universal joint or a flogged centre bearing?

[Syy0628 13]

7 minutes ago, hotwire said:

Are you sure you don't have a seized universal joint or a flogged centre bearing?

Thanks for your input, I haven't drop the exhaust and take the driveshaft off to check the U-joint yet. (Hard to do by myself  since there is no a lot of room to work under my two tiny jack stands), just want to know if I am going the right direction. 

[OP6 27]

Check your engine and gearbox mounts.

[BM WORLD 1283]

On ‎5‎/‎07‎/‎2017 at 10:39 PM, hotwire said:

Are you sure you don't have a seized universal joint or a flogged centre bearing?

have seen many e36 driveshafts where the rear uni joint has seized in one way .

[Syy0628 13]

Today I have taken the exhaust off and there is a tiny bit of play at both the center U-joint and the rear U-joint when I turn the shaft by hand, is that considered bad? I have attached a video of it.  thanks

34f2c2b442ac71c31b03529d5d9f0dfc.mp4

Edited July 8, 2017 by Syy0628
upload video

[Syy0628 13]

On 7/6/2017 at 9:47 PM, OP6 said:

Check your engine and gearbox mounts.

THANKS, but i have checked, the gearbox and engine mounts seems intact.

[Eagle 1661]

Are you grabbing one side of the joint and trying to turn the other against it? I maybe wrong but it looks like you just turning the shaft with one hand in the video

You can also support the rear subframe on axle stands and have someone run it at varying speeds. You can use the the hand brake to help too.   

[Syy0628 13]

3 hours ago, Eagle said:

Are you grabbing one side of the joint and trying to turn the other against it? I maybe wrong but it looks like you just turning the shaft with one hand in the video

You can also support the rear subframe on axle stands and have someone run it at varying speeds. You can use the the hand brake to help too.   

 

I haven't take the drive shaft off to flex it yet. The front section is locked by transmission in park, the rear is locked by diff both wheel not spinning (the wheel is on spare wheels I don't have four jack stands, which means I can't get access to the upper bolts on the flange.)When I turn the shaft, there is a tiny bit of play as shown in the video. When I loosen the bolts on the center carrier bearing, I wiggle the whole drive shaft around, the center U-joint seems to move freely in every direction.

I also like to mention that the vibration will go alway no matter how fast the speed is as long as I let off the gas. even the slightest gas will cause the vibration. It seems like is there is any torque applied to the wheel, there will be vibration. But strangely below 70kph, even I floor it in 2nd or load up the torque converter at the traffic light and then rev it to 6000rpm, there is no vibration whatsoever.  I have driven the car for 800km in total with the bad vibration, it seems to lower the threshold a bit, from 75kph to 70kph.

 I will move the jack stands to the rear to disconnect the drive shaft once I fixed the oil leak and cracked belt at the front. 

Run the car on jack stands above 70kph is quite scary, especially when the car is shaking. I think I should be the guy on the ground to see what wrong, but it will be hard to find a volunteer to be in the driver seat. I really hate it but all of my friends are not interested in car stuff at all, like those people driving with no light in the night because they never check the instrument cluster so they don't know it is black. 

Thanks for your idea. 

 

[Eagle 1661]

There is always going to be some backlash in the diff etc hence why i asked. Since you plan on taking the driveshaft out anyway im sure you find the culprit. Yeah its frustrating when you don't have anyone to help when needed.

Currently in a similar situation with my E39 driveshaft,  it has constant vibration which can be felt from about 70kph while driving, real bad a 120kph cruise but hardly feel it at very high speed. When i took the shaft out the rear CV joint was stuffed, center bearing had play and was noisy, the flex disc was cracked and very soft. The car had done 250,000km and the parts were all originals. The u-joints were still fine but i just replaced the driveshaft with a good 2nd hand one and put a new center bearing, flex disc and guide bushings it.

 

 

[BM WORLD 1283]

16 hours ago, Syy0628 said:

Today I have taken the exhaust off and there is a tiny bit of play at both the center U-joint and the rear U-joint when I turn the shaft by hand, is that considered bad? I have attached a video of it.  thanks

34f2c2b442ac71c31b03529d5d9f0dfc.mp4

unbolt the driveshaft at the diff end and check the joints for beig seized etc

[Syy0628 13]

1 hour ago, Eagle said:

There is always going to be some backlash in the diff etc hence why i asked. Since you plan on taking the driveshaft out anyway im sure you find the culprit. Yeah its frustrating when you don't have anyone to help when needed.

Currently in a similar situation with my E39 driveshaft,  it has constant vibration which can be felt from about 70kph while driving, real bad a 120kph cruise but hardly feel it at very high speed. When i took the shaft out the rear CV joint was stuffed, center bearing had play and was noisy, the flex disc was cracked and very soft. The car had done 250,000km and the parts were all originals. The u-joints were still fine but i just replaced the driveshaft with a good 2nd hand one and put a new center bearing, flex disc and guide bushings it.

 

 

I noticed the backlash in the diff, the play I mentioned is not caused by the diff backlash. When I hold the front section of the driveshaft and twist the rear half, the play is still there, I just don't know that amount of play is normal or not. 

The thing I couldn't figure out is why the vibration will stop once I let the car coast. and the vibration doesn't get noticeably worse on very highspeed.  before I took anything apart, I thought the center U-joint might be worm really bad that under load, the play causes the front half and the rear half of drive shaft to twist therefore out of alignment, that will explain the vibration stop while coasting. 

Now I can see the drive shaft, everything looks Ok, which really confuses me. 

Also, where do you get the 2nd hand driveshaft from? I was planning to find a crashed e36 from pick a part to pull a driveshaft, is the drive shaft for 5at and 4at the same? I know it's different for manual. 

My e36 is all original as well, even the cooling system... yep, the same water pump and radiator as it left the factory at 1997 and after 190000km. It is already leaking slowly from the water pump shaft, But since I got the car really cheap, I am not going to spend money on fixing it until it failed really bad. I have already spent enough money on the many chassis rubber parts. I watch the water temperature gauge more than the speedometer, so it should be fine.

e39 is more likely to tear the guide apart due to more torque from the engine, is your e39 manual? e39 is, in my opinion, the best BMW overall has ever made. Thumbs up for you to keep it on the road. 

Edited July 9, 2017 by Syy0628

[BM WORLD 1283]

have driveshafts in stock @bmworld

[Syy0628 13]

3 minutes ago, BM WORLD said:

have driveshafts in stock @bmworld

what kind of price are we talking about?

[Eagle 1661]

4 hours ago, Syy0628 said:

I noticed the backlash in the diff, the play I mentioned is not caused by the diff backlash. When I hold the front section of the driveshaft and twist the rear half, the play is still there, I just don't know that amount of play is normal or not. 

The thing I couldn't figure out is why the vibration will stop once I let the car coast. and the vibration doesn't get noticeably worse on very highspeed.  before I took anything apart, I thought the center U-joint might be worm really bad that under load, the play causes the front half and the rear half of drive shaft to twist therefore out of alignment, that will explain the vibration stop while coasting. 

Now I can see the drive shaft, everything looks Ok, which really confuses me. 

Also, where do you get the 2nd hand driveshaft from? I was planning to find a crashed e36 from pick a part to pull a driveshaft, is the drive shaft for 5at and 4at the same? I know it's different for manual. 

My e36 is all original as well, even the cooling system... yep, the same water pump and radiator as it left the factory at 1997 and after 190000km. It is already leaking slowly from the water pump shaft, But since I got the car really cheap, I am not going to spend money on fixing it until it failed really bad. I have already spent enough money on the many chassis rubber parts. I watch the water temperature gauge more than the speedometer, so it should be fine.

e39 is more likely to tear the guide apart due to more torque from the engine, is your e39 manual? e39 is, in my opinion, the best BMW overall has ever made. Thumbs up for you to keep it on the road. 

There shouldn't be any play in the joints themselves. The flex disc and center bearing can seem ok but can be worse upon removal, they all work together. Personally id just get a good 2nd hand shaft and replace everything whilst you are there, its cheap(~$200 or less) and surely you don't want to have to pull the driveshaft out again. RealOEM should help you out with what fits what. BM World or HELLBM are the goto's in Auckland i believe.

My E39 is auto, it's just a daily hack i spent too much fixing. They decent cars but the plastic quality really lets them down. I still prefer the older models.

[Syy0628 13]

Hi, it's an old thread, but I haven't really solved my problem yet, I plan to install a second-hand drive shaft to see if it will fix the problem. Is all drive shaft for e36 automatic the same? I saw a driveshaft from e36 compact 318ti for cheap. my car is e36 316i sedan, will it fit?