Drive shafts W169



Although the first defect mentioned on this page relates to a W168 it is still worth noting the problem as it can equally occur on a W169 . In the same way the second defect relates to a W169 which can equally arise on a W168 In both case the result is no drive to the drives shafts due to one having become detached from either the drive shaft intermediate Up or gearbox.


If you have Gearbox/drive problems which follow any form of repair that involves jacking the front of the car up, i.e replacement track rod ends, lower wishbone ball joints replacement struts, then please read this e-mail from Chris before doing anything further it may well save you hundreds of , see also mypage 29 where a similar even occurred.:-
Hi lofty
Sorry for the delay , have received your disc and tools many Thanks.
Ps Website is a fantastic help.

I have recently purchased a Mercedes A160 W168 with a known gearbox issue which I was hoping was not too serious.
It was jumping out of gear randomly and in any gear.
Had resigned myself to drop the engine and investigate the gearbox, This I did and may I add it is not a simple job.
Anyway once engine was out ( I had read your article on replacing drop links) and read about the chap whose drive shaft had come out and experienced a similar problem to mine all be it a sudden loss of gears in his case.

So I started to look at this and began to think this was a very similar problem but part of the shaft did not break off , The more I looked at my problem ( the bits off history I got with the car included a bill for a suspension strut replacement on the passenger side 4 months previous, Also when I pulled on the drive shaft it popped out too easily, and there was a oily deposit all around the area off the drive shaft location into gearbox.

I then took the gamble that this was the problem and put the engine back into the car making sure the drive shaft was fully located into the gear box. after replacing fluids and reverse bleeding the clutch (Ps it is an Automatic clutch)(ACS) .
And Guess what the problem is sorted it has not slipped out of gear since ....
Have enclosed some photos to go with this.
Again Thanks for the website..
Chris Fuller
The above Photo supplied by Chris clearly shows that either the drive shaft oil seal has gone defective /been damaged or the drive shaft is not correctly installed , if you have such leaks always check the correct location of the drive shaft before going further .

And another case resulting in the same problem being diagnosed.
Note I have included this defect which occurred on a w169 on this page because the defect could also apply to a W168 A class
Hi Lofty,
On Friday I had a total auto gearbox failure! While sitting at a junction I went to pull out, heard a "clunk" and the box went into "neutral" with no drive in any gear or forward or reverse. The was also a "grinding" noise in Park with the engine running.
Interestingly, there were no warning on the instrument panel, so it appears to be a "mechanical" rather than electrical/electronic failure. When I switched the engine off it still appeared to be in "neutral" even in Park and the only way it would hold was with the hand brake.
Long story short and because I have the MB Mobilo service they recovered the car and took it to the nearest MB dealer. They haven't come back to me yet with what they think is wrong, but I'm trying to decide what to do when/if they say I need a new gearbox! I bought it new and my car has only done 43000 and I've already had a gearbox valve body failure at 27000 which cost 1200 to replace, so I hate to think what they will want if it needs a new gearbox!.
I've looked at a couple of outfits on the internet who do exchange or rebuilt boxes with fitting, etc for about 2500 with a 24 month warranty and I'm wondering if you can offer an opinion or any suggestions if Mercedes says I need a new gearbox?
Thanks Ed


I immediately replied to Ed and advised him to contact the MB garage to whom his car had been taken as this was almost certainly another case of drive shaft problems.
The end product was that my Diagnoses was right, the shaft had partially withdrawn and as a result the end of the shaft was damaged to the degree that it would no longer engage in the female section of the intermediate UJ resulting in no drive to either wheel.
Even though the diagnoses of the fault was made for MB hey still charged a considerable amount of money for this repair and claimed they had not encountered this fault before.

My advise is if you suffer a total loss of drive from your gearbox check your drive shafts before even contacting a garage or get the breakdown service to check.
I would jack up each front wheel in turn and with the car in a low gear, ignition off, see if you can turn the wheels, if you can then that clearly indicates that the drive shaft is at fault You may even hear the grinding noise as Ed did also with the wheels removed it is easy to see when the drive shafts are not housed correctly. however due to the gaiter covering the intermediate UJ you will not be able to check that joint but may still be able to detect the grinding noise coming from that joint if you grip the joint with a hand.
Always support the drive shafts when for instance changing drop links this will prevent the problem above occurring on your vehicle.

Further information from Ed has indicated that the fault on his drive shaft was in the intermediate UJ situated in the near side drive shaft, where the spine had failed, this was without doubt caused by incorrect assembly when new in that the spline had never been fully housed and had only been driving on the extreme end. see photo on right which shows the end of the drive shaft spline which is damaged as well as damage to the female section of the UJ



Splines worn in the intermediate UJ situated in the off side drive shaft




















Shows the drive shaft complete




















Note that on the W169 drive shaft there is no 'C' Clip





















This shows the Intermediate UJ disassembled Note that there is a 'C'Clip on the male section of the intermediate joint and this needs to be inserted into the female section until the 'C' Clip engages in the recessed groove.




















The remaining photos show the severity of wear on the male and female sections of the intermediate UJ, so much so that drive was totally lost.































































I read the info on your disc & website and about the problems and for your and future interest, I cleaned up my drive shaft and discovered a "fault" and probably the reason it failed.
I also took it back to the dealer and spoke with the "technical foreman" who I know reasonably well and showed him the parts and he agreed, but with a 10 year old car well out of warranty, there is no way MB would consider a "claim".
You will also see in the photos my drive shaft has no circlip on the gearbox end and he said it was eliminated because it was a problem on early cars.

My drive shaft has a bracket/bearing (intermediate UJ)in the center that holds the gearbox half rigid. On the wheel side of the bracket there is a sliding joint and at the wheel end the splined shaft is fitted to mating splines in the universal joint center and held in place by an expanding spring clip. This clip holds the shaft rigid in the universal joint and all lateral movement on the wheel side of the drive shaft is taken up by the sliding center joint which, along with the U joint, is filled with grease and covered with an expanding plastic"boot".
On my failed shaft the splines on the wheel end side were basically intact, but the mating splines in the universal joint center were worn unevenly to the point that the shaft would "slip" on the teeth if pulled about half way out from the female housing.
On closer examination I could see that about 1.5mm of the splines at the back of the center piece were intact and not worn at all.
After a few experiments on the bench, fitting the shaft, clip, measuring, etc it I figured the shaft was probably never pushed fully home when it was assembled because the splines at the back of the universal joint center showed no signs of wear. Because it wasn't pushed all the way in the clip couldn't expand to hold it in and instead of all movement being taken up by the center sliding joint, the shaft was able to "move" in and out of the universal joint depending on how much "lock" was put on the steering. It was impossible to see this because it was full of grease with a "boot" over it, but when I took it apart in my de-greasing tank all the "filings" of the worn joint splines were still mixed in with the grease.

When I think about the failure, I was stopped at a junction waiting to pull out and because it was a sharp corner I had a pretty good lock on. That probably meant the shaft had probably pulled a fair way out of the universal joint and when I put my foot down to accelerate away the torque sheared what little was left of the splines and that was the "grinding" noise I could hear.
When I first took the boot off and cleaned all the grease out I could move the shaft in and out of the u joint center by hand. When I then knocked the U joint center piece all the way onto the shaft so the clip expanded, there was no way it would move and I had to use a brass hammer with some force to compress the clip and knock the shaft out.
Anyway, that's my theory, all in a day's DIY and we learn something every day!
Thanks Lofty, Cheers!
Ed



Thank you Ed, this information you have provided should save other owners a lot of money if they encounter the same problem, you point about the 'C' clip not now being fitted to the GB end off the drive shafts is noted.
As with the failure above this happened when turning the steering wheel fully left or right when the drive shaft parts are under extreme stress.
So for just once MB may be correct as I have not heard of the failure previously. Either way it is no consolation to the owners when faced with large bills for such unnecessary defects which in this case is certainly caused by incorrect assembly, albeit the car has run for 10 years with this failure/defect waiting to happen.
The replacement of drive shafts will be well within the capability of DIY owners albeit a few tools are required when the symptoms of the failure are known it is hoped that this information will do just that.
Thank you Ed for the Information and photos.








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