[BOSSBMW]

Mornin-

Seems I've been plagued by bad luck with this car recently. For no apparent reason, I began experiencing severe 'clunking' sounds from my 325i. Car only has 45k on it. I can't explain why this would happen without warning, or with such low mileage.

I jacked up the rear end yesterday and put her in Drive and turned off the DSC. It was immediately apparent that the source of the clunking was coming from the differential area. Nothing has been taken apart at this point, but my symptoms are the loud clunking/knocking sound at varying speeds, the car lounging forward slightly, computer shows no errors on the dash, but have no checked INPA.

If this is in fact the diff, what are my repair options? are all of the internals inside the diff serviceable? the list price for a whole new carrier is nearly $2k, for that kind of money I'm thinking LSD by Quaife, Wavetrac, Performance gearing, or OEM diff with shorter gears from turner motorsports (stock is 3.73, this one is 3.64).

Moreover, i'm curious if my diagnosis is accurate, or do you really have to tear the diff down to see what's up?

[BOSSBMW]

Anyone here have diff problems? can say what went wrong? please help. I'm trying to make an informed decision.

[Rockyca]

my input bearing is shot... howls like a banshee. I have a new one being shipped in from the US as we speak.

[BOSSBMW]

How many miles Rockyca? Any previous accidents? I had one two years ago. Also, I wish mine was only howling, at least then it'd be drivable. This is an extreme pounding sound while under acceleration, coasting, and braking.

[RupertPupkin]

OP start with basics. Check fluid level in diff. Could be low or have a crack somewhere and leaking out.

[Polo609]

I have the same problem, I posted in another category but should have checked here first. When I accelerate from a standstill, I get a loud metallic clank sound. If I let off the accelerator, it clanks again as the car slows down( only at slow speeds).

My neighbor thinks its a ujoint. I haven't checked under the car but that could mean a driveshaft replacement. Anyone know how hard it is to service a ujoint on our cars??

[BOSSBMW]

Polo any update on this?

does anyone have an LSD on their 325i's? experiences? recommendations?

[E90 87ss]

something to do with the dif, my car is going in tomorrow for it. I had the car on a stands and you can move the rear wheels back and forth to create the click/clank.

[BOSSBMW]

Originally Posted by E90 87ss

something to do with the dif, my car is going in tomorrow for it. I had the car on a stands and you can move the rear wheels back and forth to create the click/clank.

Did you take the car in? What's the verdict?

[N0OS3]

Originally Posted by beneliezer

Mornin-

Seems I've been plagued by bad luck with this car recently. For no apparent reason, I began experiencing severe 'clunking' sounds from my 325i. Car only has 45k on it. I can't explain why this would happen without warning, or with such low mileage.

I jacked up the rear end yesterday and put her in Drive and turned off the DSC. It was immediately apparent that the source of the clunking was coming from the differential area. Nothing has been taken apart at this point, but my symptoms are the loud clunking/knocking sound at varying speeds, the car lounging forward slightly, computer shows no errors on the dash, but have no checked INPA.

If this is in fact the diff, what are my repair options? are all of the internals inside the diff serviceable? the list price for a whole new carrier is nearly $2k, for that kind of money I'm thinking LSD by Quaife, Wavetrac, Performance gearing, or OEM diff with shorter gears from turner motorsports (stock is 3.73, this one is 3.64).

Moreover, i'm curious if my diagnosis is accurate, or do you really have to tear the diff down to see what's up?

Do you drive a 6 speed or a DCT?

Clunking or lunging could be either a chipped gear tooth or minor slippage... something i wouldn't expect from a car with only 45k miles. [mine has just under 70k and i'm just now starting to have an issue with it.]

My problem is probably not related to your case; but because i have big wheels on my car, the bushings on the suspension are wearing down because of the extra weight's momentum to keep moving foward when slowing down... this causes a softer (more of a 'roll' of the wishbones) stop and an abrupt rear-end 'kick'. In the chain of events, when the rear-end sets back while in gear, the differential gets more abuse every time i stop. (it's hard to put into words with my short vehicle vocabulary, a video would show this and make more sense)
^^all this was explained by a German Tech that's fixed the same problems in the past^^

Originally Posted by jimmydever

OP start with basics. Check fluid level in diff. Could be low or have a crack somewhere and leaking out.

The differential is a lifetime fill. If there is no obvious leakage, then there is still a sufficient fluid level.

[BOSSBMW]

Originally Posted by N0OS3

Do you drive a 6 speed or a DCT?

Clunking or lunging could be either a chipped gear tooth or minor slippage... something i wouldn't expect from a car with only 45k miles. [mine has just under 70k and i'm just now starting to have an issue with it.]

My problem is probably not related to your case; but because i have big wheels on my car, the bushings on the suspension are wearing down because of the extra weight's momentum to keep moving foward when slowing down... this causes a softer (more of a 'roll' of the wishbones) stop and an abrupt rear-end 'kick'. In the chain of events, when the rear-end sets back while in gear, the differential gets more abuse every time i stop. (it's hard to put into words with my short vehicle vocabulary, a video would show this and make more sense)
^^all this was explained by a German Tech that's fixed the same problems in the past^^




The differential is a lifetime fill. If there is no obvious leakage, then there is still a sufficient fluid level.

My car is a steptronic no signs of leakage. A colleague thinks the input bearing may be shot? I have a mechanic coming to have a look later this week, I'll keep you all posted and take pics... I hope its nothing serious, but if it is, its saving and LSD time.

[RupertPupkin]

Not to start a war but lifetime doesnt mean it will all be there. Level could still be low. It can deteriorate and I still dont buy the term "lifetime" for any liquid in any environment.

Originally Posted by N0OS3

Do you drive a 6 speed or a DCT?

Clunking or lunging could be either a chipped gear tooth or minor slippage... something i wouldn't expect from a car with only 45k miles. [mine has just under 70k and i'm just now starting to have an issue with it.]

My problem is probably not related to your case; but because i have big wheels on my car, the bushings on the suspension are wearing down because of the extra weight's momentum to keep moving foward when slowing down... this causes a softer (more of a 'roll' of the wishbones) stop and an abrupt rear-end 'kick'. In the chain of events, when the rear-end sets back while in gear, the differential gets more abuse every time i stop. (it's hard to put into words with my short vehicle vocabulary, a video would show this and make more sense)
^^all this was explained by a German Tech that's fixed the same problems in the past^^




The differential is a lifetime fill. If there is no obvious leakage, then there is still a sufficient fluid level.

[E90 87ss]

sorry guys I have a scheduling conflict so I can't leave it there... They said they need to take apart the differential and see what part needs to be replaced. I will not have it in until 4/9.

[T7R_Sky]

I had a clunking from my rear diff before. For my it was the nut on the input of the diff had started to come loose. Mine only clunked when it first set off in either forward or reverse or when load is applied after a period of no load. I wanna say its part 6 on this diagram
http://www.realoem.com/bmw/showparts...50&hg=33&fg=05

[BOSSBMW]

Originally Posted by T7R_Sky

I had a clunking from my rear diff before. For my it was the nut on the input of the diff had started to come loose. Mine only clunked when it first set off in either forward or reverse or when load is applied after a period of no load. I wanna say its part 6 on this diagram
http://www.realoem.com/bmw/showparts...50&hg=33&fg=05

well, that would certainly be a cheap fix, and disaster averted. the guys' coming to look at it this weekend so ill keep you posted.

[E90 87ss]

At the dealership waiting for CPO approval... I'll update when I pick her up... I imagine a week or so.

[E90 87ss]

Family member picked her up, they replaced the entire diff. More info later, I'm going to swap cars next week to make sure everything is well. I don't have the receipt yet but I was told it amounted to $2,200... CPO charge of $50...

[E90 87ss]

Picked up the receipt.... Brief synopsis:

1) Removed rear diff fill plug, checked for metal shaving, fluid was clean.
2) No hard spots or play from center bearing
3) Noise can be felt from the rear of the drive shaft and from the housing near the input shaft
4) Swapped drive shaft and axles from known good car, noise still present
5) Rear differential ordered and replaced, noise is no longer present

No noise, car feels great, hope this helps.

[queensfield]

E90 87ss- how many miles on your car? Congratulations on getting rid of that noise.

[E90 87ss]

Originally Posted by queensfield

E90 87ss- how many miles on your car? Congratulations on getting rid of that noise.

Thanks 60k, the noise has been present since purchase 33k... I thought it was normal until I had the vehicle on stands; When I turned the rear wheel back and forth it had a small amount of play that produced the clunking/clicking noise... U joints came to mind naturally, but you can't really see much due to the heat shields...