teerapote

Hi everybody , I have an issue with the transmission on my car it's 09 525i M sport had an 6hp21 transmission in it. it has only 30k mls (55,000km)on and it is very well maintained from day1.

if drive normally the trans shifts flawlessly 1st till 6th or 6 till 1 but if I kick it down at 100-120km/h into 4th or 5th gear it can revs all the way up to redline but it shift hard and slam into next gear and the transmission faulty light up and it stuck in 3rd gear until I shut the car off start it again the fault gone.

Exactly like this video.


Took the car to indy garage the computer stated that the C clutch and E clutch failure.

My first attemp to this was changed the trans fluid using the zf lifeguard 6 and new pan, nothing better the fault keep lighting up. ,

Seccond attemp was took off the transmission and tear it apart founded 5 clutch discs little damaged in 4 5 gears I guess, took the valve body for a look. nothing damaged the metal ball inside the valve body is nearly mint condition. done nothing with this. so I ordered the solenoid from local shop they only have the blue and yellow for 6hp19 (at first my mechanic thought that my transmission is 6hp19)

My guess was if the gear changes all fine no harsh shift or transmission slam while I drive normally(no further than 4000rpm) it has nothing to do with the solenoid.

But this is 6hp21 not 6hp19, parts for 6hp19 flooded in Thailand but no parts for 6hp21 at all.

Looked it over and over again, double check the solenoid for 3 4 5 6 gears is the same as the old ones, identical and has same part number. yellow and blue, so I can replaced it, but the 1st and 2nd solenoids is orange like the one in this video can not be found in my country so I put the old ones back.


Replacing the solenoid is easy to be done. so I've tried. replaced the 3 4 5 6 solenoids, re-assemble it all back together reset all transmission data took it for a test drive the car drives like the same. and the transmission faulty, light up like before. nothing fixed.

Prioritizing now, what should I done first? replace all solenoid(1st and 2nd solenoid not replaced yet) will get it fixed or not? or full overhaul the transmission? What is a better choice to make?

seven11

when i had a tranny issue, i was told to replace the solenoids, but i was afraid after doing them i woulds still have an issue. So i bought a used trans from eBay from a reputable seller for $1450.

JasonH

I think in this case that if the gearbox ECU is reporting a problem with the clutches that probably is the problem. The clutch plates do wear.

You say you took the gearbox apart to look at the clutches but you didn't say if you changed the plates.

If you did change the plates you must reset the gearbox adaptations using INPA or DIS 57 or ISTA/D.

teerapote

I did not change the clutch plates,don't want to randomly change the parts and took the gear box in and out a lot.

So your advice is to replace all of the clutch plates correct?

seanjordan20

Your plates should be find. As long as you had the right amount of oil in it. You should be looking at the 4 sealing sleeve gaskets and Mechatronic seal adapter. They could be bad causing the trans to loose pressure and shifts. Also the only way to check solenoids is to do a power test. take each one out and see if it is actually working. You can not just look at them and tell. You could have a solenoid that is failing.

You have 30k on car is it not still under warranty? If not start at the gaskets by replacing all 5 fill up with the correct level of oil. If that does not work then it is definitely a solenoid . I would buy a solenoid kit and be done with it.

teerapote

I already replaced yellow and blue solenoids I think it is for gear 3 4 5 6. It has identical solenoid with 6hp19 it's only I can find. the orange solenoids for 1st and 2nd gear I can't find a new parts so I didn't change them.

Is the orange solenoids causing the problem?

EDS1 2 3 4 5 6 7 What is this number for? I still wondering the EDS1 and EDS2 related to my symptoms.

seanjordan20

I found the solenoid kit for your car at ZFtranspart for $496.83. You will not find the solenoids being sold separately. You have to call them for the price and to order it. Now for the price I would just do a complete overhaul of my VB for a little more to eliminate any other possibilities. To have it rebuilt will cost around $600.

I can not tell you which solenoid controls what on you car. I have a different trans with a different set up. It could be that the solenoids that you changed did not have an issue. This is why if you are not going to test them you want to replace them all or send the VB for an overhaul.

Below with give a general ideal of how the VB is set up and what controls it. The problem is not always the solenoids.

teerapote

Thanks a lot Sean. but now I sent my car to zf branch in Thailand for full transmission overhaul. wish me luck, It is about to cost me almost 3k usd.

seanjordan20

wow, ok. At least you know it will be fixed. That is alot cheaper than we can get here in the US

teerapote

Repair in progress, will report back.

By the way, I didn't sent my car off to ZF because of the waiting list I'll to wait over weeks to get this done. So I went to transmission expert garage. The price for full transmission repair drop from 3k usd to 1.5k usd, Curious how much the overhaul kit cost exactly???