Help help help. Maybe it happened to someone. Superb 2014 4x4 haldex system failed - the rear axle started rotating with loud noises and jamming while parking. It happened twice and the system stopped working. After taking it to be checked, the haldex compass was rotten and burnt. The compass was restored, a new pump was replaced. The service was done, the filters were changed. The system works as intended. However, from time to time I notice a "rattling" in the rear reducer but only for a short period of time, like 2s. accelerating quickly. A weaker vibration repeats when switching gears 5 and 6, again briefly as soon as the revs rise to 2k. Has anyone experienced this? Any ideas on where to start checking? Won't there be loose cogs or something after finding the problem?

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Yeah, my bad

 

Help help help. Maybe it happened to someone. Superb 2014 4x4 haldex system failed - the rear axle started rotating with loud noises and jamming while parking. It happened twice and the system stopped working. After taking it to be checked, the haldex compass was rotten and burnt. The compass was restored, a new pump was replaced. The service was done, the filters were changed. The system works as intended. However, from time to time I notice a "rattling" in the rear reducer but only for a short period of time, like 2s. accelerating quickly. A weaker vibration repeats when switching gears 5 and 6, again briefly as soon as the revs rise to 2k. Has anyone experienced this? Any ideas on where to start checking? Won't there be loose cogs or something after finding the problem?

Let's assume that haldex is ok.

 

Then I would check the following that might give similar symptoms:

1. Check the rear ad front flexible discs on the propshaft. (called hardy flexible disc). These are made of rubber inside steel housing and intended to reduce vibration under use. But when they are worn, the rubber will loose from steel frame and cause rattling and/or vibration.

 

2. Next I would check are the rear differential oil level. If that is low, find the cause. Could be a bad rear diff seal (right and left drive axle). To low on diff oil will destroy your rear diff pretty fast and the solution is to repace whole rear diff. Expensive, very expensive if bought new from dealer. Used are cheaper. If low level, fill up to specs.

 

3. If oil levels are good and no metallic parts came out after draining and still there is a vibraton humming sound insde cabin during use, well, then I wuld check the bearing races inside the rear diff. But to do that you need do take the whole assebly down and open up the rear diff. It is actually quite easy, but you will need some tools to do it. Well, right/left side has bearings and races. If they are bad, they can be replaced for under 50GBP. If they are bad or worn, well that will make constant humming sounds. Doesn't look like it based on your symptoms though.

 

My guess without inspecting you car would be to check nr 1 and then nr 2.

 

How do I know this? Well yes, you guesed it, I have replaced hardy connection disc, haldex service and inspected the inner races on my rear diff...Its quite a job, but for a serious DYI it is manageable in you own home garage. Just time consuming :-)

Anyway, do fill up the rear diff oil level to specs anyway. It is a good precaution. If you have leaks from the seals, it is likely that you have water inside your rear diff and that is never a good thing.

 

Replacing the whole unit at a dealership will likely cost you more than 4000 GBP, even more as well (norwegian prices for parts and labour). Dealership does not automatically replace races and bearing on the ear diff, ince they are supposed to be sealed "for life". Besides, any repairs done, they have to give assurance that it will not fail again, and that is not a guarantee that dealership will stand by. So, in short; they replace the whole unit (rear diff complete with haldex) as a first measure.

Water will not enter the diff through a leaking seal unless the vehicle is submerged.

 

@rbhelle Do you have codes or part numbers for the crown wheel bearings?

 

More importantly did you manage to find a source for the oil seals?

 

@Edguzia Did you mean Haldex "controller" and not "compass"?

 

What do you mean by "the rear reducer"? - differential or exhaust perhaps?

 @J.R. Hi. My rear diff had water in oil due to a faulty seal rear left side. On inspection of the seal and the rear diff internals there was water and i cannot see where else came from. I will post pics in a minute.

Bearing partsnumbers: 

My rear diff partnr is a:  0BR 525 010B

Bearing right and left:  www.LBMautoparts.com

Partnumber: LM45854/LM48510 and 503349/503310

I opted not to buy pinion ring bearings since that operation is very difficult when it comes to correct distance on mounting. Need very specialtools that I dont have and wont buy. Besides, the pinion bearings are not exposed to same tear and wear as the outer bearings.

 

Partnr 1

https://lbmautoparts.com/search?q=503349%2F503310&searchfld=

Partnr 2

https://lbmautoparts.com/search?q=LM48510&searchfld=

 

Leaking seal.

As of the issue with source to water. My assumption is that there are only 2 ways water will enter into the rear diff. Either from bad seals or via the venting tubes. My conclusion based on inspection, it was bad seals. If one drives 1000km through rain, wet snow and generally bad norwegian weather for like 12 hours in one leg, as I did. Well, that should be enough to get water inside. 

Rear reducer must be exhaust. Rattling from that could be connected to bad exhaust mountings or faulty, sloppy job? The exhaust must come down to access the haldex clutch plates. Could also be that the exhaust connection joint is somewhat misplaced so they touch the frame during acceleration? Easy fix, just undo bolts and realign.

@rbhelle Thanks for thorough explanation. I did more thinking and experimenting so situation is as it follows: Today i intentionally recreated those situations, and made sure that this rattling sounds appear when wheels are almost turnt left or right and you accelerate. When you start going straight, no sounds. So what is the connection between turnt front wheels and rear axle? Which exact place could be rattling?

P.S

While the haldex was broken, i had only FWD, and there was not any sounds from the back. They appeared only when Haldex was back online. Any thoughts?

@J.R. That could be a language barrier  It would be differential, yes. Maybe you have any thoughts on my last update?

 

 

6 minutes ago, Edguzia said:

@rbhelle Thanks for thorough explanation. I did more thinking and experimenting so situation is as it follows: Today i intentionally recreated those situations, and made sure that this rattling sounds appear when wheels are almost turnt left or right and you accelerate. When you start going straight, no sounds. So what is the connection between turnt front wheels and rear axle? Which exact place could be rattling?

P.S

While the haldex was broken, i had only FWD, and there was not any sounds from the back. They appeared only when Haldex was back online. Any thoughts?

Hmm, well, that opens up a wide array of possibilities 😄

Pre condition: All bolts are tightened to specs on wheels, axle nut and bolts on/in/around knuckle.

Checked your wheel bearing for tear and wear?

What about your inner/outer drive shaft joints? They are also prone to wear and tear and will cause both rattling, humming sounds and even a lockup might happen since inner outer cv joints have ball bearings inhouse.

My take now since it happens during hard left/right turn during acceleration is: cc joints inner or outer 😅

@rbhelle I see that my haldex journey id far from over 🙌 Pardon my mechanic knowledge, what are cc joints?

2 minutes ago, Edguzia said:

@rbhelle I see that my haldex journey id far from over 🙌 Pardon my mechanic knowledge, what are cc joints?

Oh, my mistake, typo. CV joint, not cc 😅

3 minutes ago, Edguzia said:

@rbhelle I see that my haldex journey id far from over 🙌 Pardon my mechanic knowledge, what are cc joints?

Well, it is extremely difficult to diagnose via internet...

But I always take into consideration that all bolts, joints and mechanics are actually tightened to specs and assembled according to manufacturers specs. If that is correct, then it is easier to actually fsult find what part it could be based on specific symptoms connected to a specific driving condition. If only present when turning steering wheel all to the left OR to the right AND hard acceleration. It makes it more plausible to be a fault in the drive line connected to inner outer CV joints, drive shafts or wheel bearings. But one cannot rule out that is is stabilizer, anti roll bar as well. But often those parts do not tend to provoke a "wheel lock up" like feeling. But really bad CV joints and/or really bad wheel bearings might do that. I suggest you get car up on stands and do a thorough inspection, both physically and looks. 

I have of course ruled out that you recently had a diagnose with advanced code reader? That is of course the very first thing to do no matter what symptoms one gets 🙂 It is no good that this was done last week, month or before this actual symptom you are experiencing right now 😊

Hope you get it sorted out in the end. VAG cars can be a pain to fault find without a proper diagnose tool. Vcds or obd11 are the 2 affordable tools that has industry leading tech and are officially supported by VW group besides Odis.

Are of course other brands, but not as good and accurate as VCDS/OBD11 when it comes to user interface similar to ODIS (factory tool) imho....

Anyway, I would listen to what @J.R. has to say. He is a mechanic and probably knows a lot more since he was or is a professional mechanic 🙂

2 hours ago, rbhelle said:

If one drives 1000km through rain, wet snow and generally bad norwegian weather for like 12 hours in one leg, as I did. Well, that should be enough to get water inside. 

 

Forgive me, I forgot about your climate

 

Did you replace the seals and what were the part numbers, I have yet to find a source for them.

23 minutes ago, J.R. said:

 

Forgive me, I forgot about your climate

 

Did you replace the seals and what were the part numbers, I have yet to find a source for them.

Yeah, did them both since 1 was bad. Oh, them partnumbers....hmm, front bevelbox use the same, as rear, but there were different partnumbers left right side if I remember correct.

 

02D 525 596 B/F is for right side (i used Elring 871.180) and I do believe 09A 409 529 B/C is for left side (Elring 877.460).

But do checkparts catalogue etka. 

 

Thats brilliant thanks!

 

Looks like I will be biting the bullet and dropping the rear subframe this summer.

On 15/01/2025 at 19:07, rbhelle said:

Well, it is extremely difficult to diagnose via internet...

But I always take into consideration that all bolts, joints and mechanics are actually tightened to specs and assembled according to manufacturers specs. If that is correct, then it is easier to actually fsult find what part it could be based on specific symptoms connected to a specific driving condition. If only present when turning steering wheel all to the left OR to the right AND hard acceleration. It makes it more plausible to be a fault in the drive line connected to inner outer CV joints, drive shafts or wheel bearings. But one cannot rule out that is is stabilizer, anti roll bar as well. But often those parts do not tend to provoke a "wheel lock up" like feeling. But really bad CV joints and/or really bad wheel bearings might do that. I suggest you get car up on stands and do a thorough inspection, both physically and looks. 

I have of course ruled out that you recently had a diagnose with advanced code reader? That is of course the very first thing to do no matter what symptoms one gets 🙂 It is no good that this was done last week, month or before this actual symptom you are experiencing right now 😊

Hope you get it sorted out in the end. VAG cars can be a pain to fault find without a proper diagnose tool. Vcds or obd11 are the 2 affordable tools that has industry leading tech and are officially supported by VW group besides Odis.

Are of course other brands, but not as good and accurate as VCDS/OBD11 when it comes to user interface similar to ODIS (factory tool) imho....

Thanks, probably will start from CV joints. Further experiencing the problem, so yes locking, rattling sound gets harder the more you turn the wheels. Of course with condition you push gas pedal. If you just let it roll in drive, no sounds. No sounds also when you do tight corner with accelerating. No sounds. Only from the stationary position. But i guess I am lucky that I am not in Norway, because used differential costs like 300 ( if i need to change ) and both CV joints could be replaced for additional 300, so maybe not as bas as in your place. Thank you very much!

@Edguzia Oh, the price I got is for factory new. Used ones with low mileage is around 200-300 Gbp, same as in UK. If you just replace the bearings, you get those for like 50Gbp. But to replace, you will need a bearing extractor ad of course some tube sealant. But that is very doable. Here is a video on how to do it. But do notice, this guy takes down the whole subframe. You dont need to do that. In elsawin, that is not the described way on my superb. You just take down the rear diff and haldex as a whole unit.

Rear diff is mounted to subframe with only 3 xzn screws. 2 of them reachable from the rear boot bottom behind some rubber seals. Or there are markings on where to drill 2 holes exactly above the screws. Drill hole and just cover them up with rubber seals after done. The last xzn screw is reachable from under the car. Only stuff that has to come off are the anti roll bar, rear drive axles and both springs and the propshaft joint to the haldex. Saves you a lot of time vs taking whole subframe down.

Below is a video on how to service the bearings and races.

 

Oh, yes, the rear exhaust has to come down. I used a gearbox jack to support all things.

But, be aware, If you dont have a lifter, you do need some big jack stands to get the car at least 45-50cm off the ground.