[moshii]

Hi friends,

2012 535ix (Automatic) with clunky/jerking problem at something like 8 mph and again at about 21 mph (slightly less) then completely fine at higher speeds.

It's started at about 125,000 miles. Currently at 130,000. Replaced transmission fluid, pan and filter when it first started happening and it did not help. It wasn't that bad then so I ignored it. Gradually it seems to be getting worse and now its is bothering me enough that I cannot just ignore anymore.

I tried the "Reset Driver Memory" as described here. The problem does not go away entirely but it does seem to help a lot but only temporarily. Switching to sport mode makes the clunking/jerking worse.

Will getting it "flash" coded help? Custom tuning?
Should I try the dealership for engine transmission software update? (Never had any sort of software update)

Will any of these solve the issue? Advice please, thank you!

[Trainwreck914]

Did you check the transmission mounts?

[mashpotato]

if it is the tranny internals. You can check clutch fill pressure (indicate wear) through ISTA-D, XHP and some other apps. My tranny is not doing so well on downshift to lower gears. For the 8 speed is 5 clutches: I read somewhere good performance <180mBar, ok <300mBar, just operational is <750mBar (XHP recommends).

Flashing might help a bit, but in the end it cannot fix wear and tear (for me its too late to change tranny oil). So you have to rebuild your valve body or other fixes.

[moshii]

Went to the dealership and asked for engine and transmission software update. They did something called 1.5 Program (that's all it says on the service sheet). This 1.5 Program unfortunately hasn't resolved the clunking/jerking.

Inspection & recommendations show I need to replace the drivetrain flex disc and change the oil for the transfer case.

I keep getting a Drivetrain malfunction warning that says, "Drive moderately maximum output not available" which I've never had before the update. Car won't go over 20 mph when this happens but it goes away when I restart the car. The warning keeps coming back though....

I hope replacing the flex disc and changing out the oil like dealer recommend will fix all the issues....

[moshii]

Originally Posted by mashpotato

if it is the tranny internals. You can check clutch fill pressure (indicate wear) through ISTA-D, XHP and some other apps. My tranny is not doing so well on downshift to lower gears. For the 8 speed is 5 clutches: I read somewhere good performance <180mBar, ok <300mBar, just operational is <750mBar (XHP recommends).

Flashing might help a bit, but in the end it cannot fix wear and tear (for me its too late to change tranny oil). So you have to rebuild your valve body or other fixes.

Thank you I will get this checked

[moshii]

Originally Posted by Trainwreck914

Did you check the transmission mounts?

Transmission mounts no problem

[dzz]

bad engine mounts, bad transmission mounts, driveshaft issues? Just some of the things that could cause vibration

[RConnor535i]

Changing the Vanos solenoids fixed my jerking and stuff