sventastic82

I need a little help to identify this whining noise.




I think it is the differential.
The noise changes with speed and load if I get off the gas the noise gets louder.
It doesn't change with engine RPM or if I shift through the gears not even in neutral.




I performed the differential oil change about 12k miles ago but no improvement on the noise.


Does any of you know where the noise could come from besides the differential?

mthis

Videos private

what type of tires do u use?

sventastic82

Dunlop dz102

Sorry forgot to publish the video.

Rolf de Graaff

Do you have lsd? I have a P30 with factory lsd and it makes the same noise. I also have the sound like a flappering baseball card thru spokes as discussed in another thread. I don't know what it is, maybe worn bearings?

sventastic82

Don't have the factory LSD at least as much as I know. The option of the car don't show it.
How can I mechanically identify that?

That is what I'm thinking a worn bearing.
I guess I wait until it gets really bad before I pull the diff and replace the bearings. Maybe I go LSD since I have to open it up anyway.

Johnnie58

Doesn't sound like a diff noise to me , sounds like a drive shaft cv or wheel bearing from my I pad , just saying , it sounds too high pitched to be a crown wheels or etc

Rolf de Graaff

Is there an easy way to check that?

Jasonoff

Gear whine is high pitched.

Find out out what type of differential it is. You did the oil change without knowing which diff it was, so what type of oil did you use?

sventastic82

Thanks for the feedback.

I have mounted the camera in different location near the diff, the transmission and torque converter. The noise seams to be most noticeable at the diff.

That is why I thought it is the diff.
Beside that the noise goes away when I let off the gas.
I thought it shouldn't be a wheel bearing since the noise would be the same with or w/o engine load.
And the noise is close to the center of the car a wheel bearing would be on one or the other side of the car unless two bearings are going bad.

Just to make sure I'll take some more videos close to the wheels.

roadtalontsi

baseball card noise is parking brake springs and clip. Theres updated parts in a bulletin, or your 3 piece wheels coming apart (if you have aftermarket ones )

That noise does sound a little loud, but whats it like in the car? It's normal for some noise coming from parts moving at high speeds. Your best bet is to put the car on jack stands, put the car in dyno mode and use a stethoscope or even a rubber vacuum line to locate the noise source. Theres also a carrier bearing in the middle of the driveshaft as well. Doesnt sound like tires to me.

sventastic82

That is the oil I used Castrol SAF-XJ 75w140
Is the LSD using a different oil?

sventastic82

The noise overcomes the engine sound going over 70mph or when slowing down.
I like the rubber vacuum line tip. Thank you!

Yeah it's not the tires I tried differ pressures and a new set of tires w/o a change in noise.

Rolf de Graaff

Thanks for the info , I will check this out.

CarPartsDiscount.com

IF the sound is coming from the diff then i would assume a bad bearing or best case scenario it is just low on oil. have you noticed any leaks?

Rolf de Graaff

Is it easy to change the oil? Does the car have to be raised, or can I do this at home?

sventastic82

It is the differential.
I jacked the car up and ran it up to 60mph.
And the whine is overcoming the ingine noise. When I crawled under the car it came from inside the differential for sure.
Looks like I'm going to rebuild the differential and while I'm at it upgrade it to an LSD.

Thanks for all the advise and help.

Jasonoff

I'd pull the cover and inspect.

sventastic82

I thought about it. But that requires taking down the differential if I'm not mistaking.
Which I'm going to do anyway to rebuild and upgrade it.
If it's looking good then I can still send the parts back which don't need to use.

sventastic82

I received the Quaife differential.
Thanks ECS.

Would have been better if the Fed Ex driver is able to read, he delivered the $1300 package to a wrong address half mile down the road. Luckily I saw him drive by and checked the tracking # which stated delivered. That meant delivered to the wrong address. I jumped in the car and drove down the road and saw the package sitting on someone else's porch and grabbed it. (I did not get shot at)

PARADOX_sf

I am having the same problem with w219 CLS with P30 option. Did you solved this problem?

sventastic82

Yes It ended up being bad pinion gear bearings.

PARADOX_sf

I've found the problem. When the differential is fitted with lsd, the lsd unit creates a lot of metallic particle which circulates through the oil. The differential was not fitted with magnet plugs and all of these metallic particles damaged all of the bearings. It is extremely important to change the diff oil regularly then it has lsd unit installed. On my unit the oil never has been changed. All the bearings are bad. I may post some photos later. The lsd unit is worn out too. It need a rebuild. The unit has more clutches and plates compared to bmw 188 and 210. The clutches and plate are the same as ZF 188 lsd unit. The ramps are 50/90 deg with 50nm static load. I believe the unit is 40% lock up.

PARADOX_sf

Photos

todthedod

I know this post is a couple months old, but I have a noise coming from the rear of my car. It's hard to describe the sound, but imagine you have a flat-spotted tire. It sounds like that but the frequency is shorter than the circumference of the tire. So with one revolution of the tire, I would hear the woompwoomp sound maybe 2x. (estimate) . To me it sounds like it's coming more from the right rear so I did change the right rear wheel bearing but it's still there. It's gradually getting louder and louder. it's been doing it awhile so I figured while I'm not driving it in the winter, I'll try to diagnose.

Just want to see what are the possiblities so I can do a visual inspection. I know the lsd is probably the culprit but don't want to order one unless I'm sure. What else should I check back there? Already changed the diff oil and it didn't change the sound at all.

sventastic82

If it is noticeable at low speed, I would jack the rear up and put the car in neutral and start moving things by hand to see if the noise can be replicated.