Rebuild of my 2004 525i E60 6HP19 valve body transmission fault

[reegz]

I had recently fixed my ZF 6HP19 gearbox in my 2004 BMW 525i E60 and utilised the collective knowledge of the internet including this and many other forums to diagnose and rebuild the transmission and thought I might do this write up to give others insight that may have encountered similar issues as I didnt find many others with quite the same symptoms or remedy as mine.


I bought the car at auction (before realising this auction place seems to be mainly a dumping ground for dealers with problematic cars) and I drove the car home conservativly 45 mins without any issues. It was later when I took it for a drive and about 15 mins in I was doing maybe 60kph and accelerated to overtake, transmission drops down a gear (5th to 4th) & thats when the car chimed at me with a transmission fault warning and went into limp mode. I turned the engine off, started it up again and it seemed to drive ok unless I accelerate med-hard. I take it for a drive the next day and accelrate hard and its fine, 10-15 mins into the drive it does it again so it seems to ony occur when the fluid is hot as a few tests revealed it runs pretty well when cool. I had also noticed some not so smooth shifts which werent too bad but also a bit of a 2-1 gear shift clunk. I still drove the car occasionally and it ran ok if I drove conservativly, one time at the lights I went to move forward and I had no power, heard a noise like fluid moving through the pipes but not quite pushing the car forward, turned off and on again and it ran ok again but not great. Kinda sounded like it was low on fluid.


another symptom was a bit of a delay moving from reverse to drive and park to reverse and a mild clunk as I went to take off.


I really didnt want to fix the box myself but I also didnt want to spend $1000 just for a mechanic or trans specialist to take a guess at the problem then even more $ for parts and labour towards a potentially unecessary part that wont resolve the issue (as I had read many others experience this) so I figured I will have to do it. Car has 150,000 K's on the odo and I check the fluid, its black and smells burnt, probably never changed since new and the burnt smell concerns me some internal damage has occured, I really didnt wanna go all in fixing it and decided I would change the fluid and hope it would help the fluid was low also and maybe it would resolve the issue. changed the fluid and topped it up to the proper lever, ran good cold then trans fault warning again.


FYI ZF lifeguard fluid is not so commonly stocked here in Australia and very expensive so I sourced some Gulf Western Syntrans fluid as I hear its a good alternative, 20 litres of it was $150 delivered direct from GW


checked the codes and got 4F85 - Ratio montoring, clutch E
4F8D - Ratio montoring, gearshift 5-4
4F8E - Ratio montoring, gearshift 4-3


seems maybe I,m getting clutch slip, sometimes not so smooth gear shifts (but not that bad) and 2-1 clunk, my search online reveals a hundred possibilities such as torque converter, flex disc, input shaft bearing etc.


here are two good resources for these gearboxes:
https://sayyarti.wordpress.com/2015/...ission-issues/
http://www.bmwlogicseven.com/?p=3738


The latter pretty much repeatedly recommends to rebuild your valve body.


After reading up much about it I had come to the conclusion the main culprit was the mechatronics seal adapter was probably the issue due to it only occuring at temperature so I purchased one ready to do the change. but if I'm going to all the effort of pulling the transmission apart just for this and thats not the underlying issue or there are other contributing factors I'd be pretty annoyed to have to get under there again so I figure I may as well do it properly and rebuild the valve body, replace solenoids and other seals, although I'm concerned I may have done more damage to the clutches already I spent about $1000 on these parts:


mechatronics seal adapter (figure 8 looking plastic thingy) my main area of concern as they are a common fault
4 rubber tube seals that connect to the valve body - they also wear down after time
7 new solenoids - these have alot to do with gear shift issues
guide sleeve/seal for mechatronics electronics connection - although mine wasnt leaking its a common issue and its fairly inexpensive
Sonnax zip kit - to rebuild the internals of the valve body, mine looked good so I'm not sure how much help this did for me
seperator plate for the valve body halves (required if pulling the valve body apart as old one is not reusable)
New transmission oil pan and inbuilt filter


Upon pulling off the pan I didnt find any clutch fragments and very few metal dust stuck to the magnets so I felt good about there being minimal clutch or gear damage. I followed various youtube tutorials to rebuild this and replace all the parts and it wasnt too difficult but not easy, put it all back together and fill the box with fresh fluid from the 20l GW syntrans drum I bought previously then reset adaptations.


I have been testing the car about 100 kilometers now and it has driven beautifully, smoothest gear shifts (except first few k's as adaptations were learning) and no 2-1 clunk, no slipping or errors on hard acceleration and fast gears change from park to reverse and reverse to drive without a jolt as I move forward.


I am really happy with the outcome after all the time and $ now to move onto the other endless series of issues with this vehicle.

[MarcoZandrini]

Great post! Glad everything worked out for you. Now, enjoy the car as you’ve earned it.