S5 2009 strange gearbox behaviour/jerk

[whiteho2]

Hi everyone,

I’m hoping someone can shed some light on my problems.

My 2009 S5 which has done 72k, has developed a strange jerking after coming to temperature. It has the 7 speed S-Tronic box.

There are two main issues:

Firstly, after driving through stop/start traffic the car develops a jerk after coming to a full stop. This is not evident when the car is cold and less so if I’m doing a faster, more continuous cruise. The jerk relates to the revs dropping for a moment, like it might stall. Weird.

Secondly, when pulling off, the car jerks like I’m driving a manual and I don’t know how to use the clutch - highly irritating and frankly it’s ruining the driving experience. It like it can’t apply the power correctly.

like I said, this is highly irritating and most advise I’ve received is to sell it now.
I must add, the car was recently serviced and the gearbox oil changed. My log book has no evidence of this ever being done, butthe problem existed before the service and I think it’s got worse since.

At speed in the cruise, the car drives beautifully but this is getting so bad now that I really dont know what else to do!!

All ideas are very much welcome!

Thank you

 

[whiteho2]

Anyone?

 

[Dippy]

Have a search on the various Audi forums and you'll soon come across tales of woe for this gearbox. This is one of the most comprehensive threads but there are others. Audi revised it in 2011/12 and again in 2013. The 2009/10 boxes have most reports and of those the ones that were never serviced seem to be the worst.

 

[ninjag]

Hi everyone,

I’m hoping someone can shed some light on my problems.

My 2009 S5 which has done 72k, has developed a strange jerking after coming to temperature. It has the 7 speed S-Tronic box.

There are two main issues:

Firstly, after driving through stop/start traffic the car develops a jerk after coming to a full stop. This is not evident when the car is cold and less so if I’m doing a faster, more continuous cruise. The jerk relates to the revs dropping for a moment, like it might stall. Weird.

Secondly, when pulling off, the car jerks like I’m driving a manual and I don’t know how to use the clutch - highly irritating and frankly it’s ruining the driving experience. It like it can’t apply the power correctly.

like I said, this is highly irritating and most advise I’ve received is to sell it now.
I must add, the car was recently serviced and the gearbox oil changed. My log book has no evidence of this ever being done, butthe problem existed before the service and I think it’s got worse since.

At speed in the cruise, the car drives beautifully but this is getting so bad now that I really dont know what else to do!!

All ideas are very much welcome!

Thank you

Who serviced it and changed the fluid?

 

[whiteho2]

Who serviced it and changed the fluid?

Just a local guy I use for servicing.

 

[ninjag]

Just a local guy I use for servicing.

The first things which come to mind to check are:

• Mileage of each transmission fluid change
• Was the correct spec fluid used for the mechatronics unit
• Was the correct filling process used (i.e. the temperature bit)

If it were me I would probably do the fluid and external filter again myself and also have a look at the fluid. I mind seeing a video where the colour could indicate if the correct fluid is in it. If it looks like the wrong fluid, or is ****** (smell will be bad) then I'd probably drop the pan and replace the internal filter as well.

Has the actual gearbox, transfer case and front diff fluid been changed? If not it could be worth doing that first (I'm assuming the S5 is the same as the S4).

Good luck with this, I'm constantly paranoid about my DSG because Audi lies about the service history and mine never had the fluid changed at 38k miles. They came out with excuses... ****** main dealers. I did it myself at 60k miles when I bought the car and I'm hoping I've escaped any issues.

 

[whiteho2]

The first things which come to mind to check are:

• Mileage of each transmission fluid change
• Was the correct spec fluid used for the mechatronics unit
• Was the correct filling process used (i.e. the temperature bit)

If it were me I would probably do the fluid and external filter again myself and also have a look at the fluid. I mind seeing a video where the colour could indicate if the correct fluid is in it. If it looks like the wrong fluid, or is ****** (smell will be bad) then I'd probably drop the pan and replace the internal filter as well.

Has the actual gearbox, transfer case and front diff fluid been changed? If not it could be worth doing that first (I'm assuming the S5 is the same as the S4).

Good luck with this, I'm constantly paranoid about my DSG because Audi lies about the service history and mine never had the fluid changed at 38k miles. They came out with excuses... ****** main dealers. I did it myself at 60k miles when I bought the car and I'm hoping I've escaped any issues.

Hi thanks for the detailed response, much appreciated.

I believe the correct fluid was used as he contacted Audi for all of it. However, what do you mean by ‘the temperature bit’ because admittedly even I don’t know about anything to do with that!!

As much as I’d love to read up and attempt myself so I know it’s done right, I don’t have a driveway so it’s difficult. I’d happily pay again to get it done right, especially someone who definitely knows Audis and what’s required. I’m in south west London so might look for a specialist.

As for frequency of oil change, it’s weirdly been serviced by Audi in its early life but according to the service book, not changed. Im on 70k now so I sincerely hope this wasn’t the first change.

Thanks so much for the advice.

 

[ninjag]

Hi thanks for the detailed response, much appreciated.

I believe the correct fluid was used as he contacted Audi for all of it. However, what do you mean by ‘the temperature bit’ because admittedly even I don’t know about anything to do with that!!

As much as I’d love to read up and attempt myself so I know it’s done right, I don’t have a driveway so it’s difficult. I’d happily pay again to get it done right, especially someone who definitely knows Audis and what’s required. I’m in south west London so might look for a specialist.

As for frequency of oil change, it’s weirdly been serviced by Audi in its early life but according to the service book, not changed. Im on 70k now so I sincerely hope this wasn’t the first change.

Thanks so much for the advice.

Apparently, if it's not specifically mentioned in the service history then there's a pretty good possibly that it was never done as it's classed as an optional thing or something, so doesn't prevent the service history from showing as complete. Very deceptive in my opinion.

You could do what I did and call all the previous places who serviced it and ask if the DSG fluid was done?

The temperature thing is where you cold fill the transmission until it starts to pour out then screw the drain plug on by hand. Start the car and monitor the transmission temperature with a scan tool until it reaches 40 degrees I think it is (need to double check temp), then quickly remove drain plug and fill with more fluid until it starts coming out then screw it back in.

If he didn't do the final bit then it may have been running with too little fluid?

 

[weemanno1]

Hi everyone,

I’m hoping someone can shed some light on my problems.

My 2009 S5 which has done 72k, has developed a strange jerking after coming to temperature. It has the 7 speed S-Tronic box.

There are two main issues:

Firstly, after driving through stop/start traffic the car develops a jerk after coming to a full stop. This is not evident when the car is cold and less so if I’m doing a faster, more continuous cruise. The jerk relates to the revs dropping for a moment, like it might stall. Weird.

Secondly, when pulling off, the car jerks like I’m driving a manual and I don’t know how to use the clutch - highly irritating and frankly it’s ruining the driving experience. It like it can’t apply the power correctly.

like I said, this is highly irritating and most advise I’ve received is to sell it now.
I must add, the car was recently serviced and the gearbox oil changed. My log book has no evidence of this ever being done, butthe problem existed before the service and I think it’s got worse since.

At speed in the cruise, the car drives beautifully but this is getting so bad now that I really dont know what else to do!!

All ideas are very much welcome!

Thank you

i have just posted about the same thing happening to me! but mine is 2011 but if you read my thread it might help you

 

[weemanno1]

my issue with your same symptoms. this is a link if it helps

 

[whiteho2]

my issue with your same symptoms. this is a link if it helps

Thanks weemanno1!
So your issue was not only the sensor but mainly the solenoid?
So overall was getting your mechatronic unit repaired actually necessary in the end?

It seems that the exact symptoms I’m experiencing are the same as what you had prior to that solenoid being changed.

Another weird symptom I sometimes get when the cars hot is the gearbox will go into reverse, but there isn’t enough torque to actually move the car backwards and it’s almost like it wants to stall, although the engine won’t let it.

I might look into this solenoid and also get the gearbox oil changed again, with the advice about letting it warm to 40c prior to topping up once more.

Thank you!!

 

[whiteho2]

Apparently, if it's not specifically mentioned in the service history then there's a pretty good possibly that it was never done as it's classed as an optional thing or something, so doesn't prevent the service history from showing as complete. Very deceptive in my opinion.

You could do what I did and call all the previous places who serviced it and ask if the DSG fluid was done?

The temperature thing is where you cold fill the transmission until it starts to pour out then screw the drain plug on by hand. Start the car and monitor the transmission temperature with a scan tool until it reaches 40 degrees I think it is (need to double check temp), then quickly remove drain plug and fill with more fluid until it starts coming out then screw it back in.

If he didn't do the final bit then it may have been running with too little fluid?

Very interesting. I wasn’t aware of this. I will get this done again and also look into the solenoid change mentioned below.

thank you!

 

[ninjag]

Very interesting. I wasn’t aware of this. I will get this done again and also look into the solenoid change mentioned below.

thank you!

No worries, this is a great page on the transmission including a video on servicing it: https://andybucks5.blogspot.com/2018/08/audi-s-tronic-gearbox-reliability-faults-tuning-repair.html

Mind that there is two separate fluids/oil required for the 0B5 gearbox and it may be worth changing the hypoid gear oil as well which is for the gears, transfer case and front diff. It's claimed to be lifetime, but I'll be doing mine at about 70-80k miles. I believe you'll need something to support the transmission though for this job though.

Part of me wishes it was the ZF8 transmission instead, but then my XF had this and at 80k miles it started showing problems even after a fluid change, where we also noticed that the original fluid was ****** and there was a strange metallic paste over the magnets and pan filter.

 

[ninjag]

Here's the fluid/oil split if you don't already have this:

 

[ninjag]

I'm not sure why but in my previous post I said that the fluid was ****** and it's been auto censored?

lol, I'm trying to say "c o o k e d"

 

[weemanno1]

Very interesting. I wasn’t aware of this. I will get this done again and also look into the solenoid change mentioned below.

thank you!

the fix for mine i believe was the oil prossure solenoid all along.. but if its got to come out i would replace the kit that vag supply but be aware it was originally designed for inhouse repairs so one kit fixes differant issues but it you get the kit and that solenoid. if your brave just replace that solenoid. the re adapt and retest. if not pull it back out and replace the kit. along with some fresh oil you should be sound. servicing it and adaptions did not fix my issue.. i would get your gearbox adapted 1st,, it will run fine for about 150 miles before playing up if this happens i would move to the solenoid replacement if you have no codes (only code i had once was cannot regulate gear selector 2 pressure.,.. if you have codes replace with mech repair kit and this solenoid. anything over and above this is sadly a rebuilt or new mech unit. which milta would be your people! but cheapest repair 1st . Interestingly i also found after replacing the gearbox mount insert with the billet aluminium one mine was 100 times worse!. i have pics i'll post.

Below is an image of my old one you can see the tab has gone all yellow and the seal has failed letting fluid pressure drop. compared to the new one above which is a snug fit and has extra thick seal on it.