Hi,
Thinking of installing new Solenoid Pack at next Service. Issue is Jolt on up-shift from 5th to 6th but worse issue is it gets 'stuck' in 4th gear when hard acceleration through the gears, resulting in very disconcerting huge jolt and engine revs screaming. Also, had on occasion all Gears show up on indicator in dash binnacle and the whole whole gearbox being stuck in the present gear and not being able to shift up or down until I pull over, stop and turn engine off and on again.
2005 with 61000 on clock. Had Gearbox oil changed and values reset. No fault codes showing when recently plugged in via a Bentley Specialist.
Next step i'm thinking just to swap the solenoids out at next service as this is a relatively quick cheap fix as part of the diagnosis/fix process. Any agreements or thoughts?
Thanks

 

Hello @bmw5series ,
I just wanted to ask, before you jump into the innards of the transmission itself, how is your shifter dust cover, as some of your descriptions of issues sounds like a faulty broken dust cover, whereas the magnets in said dust cover are not functioning as they should, therefore not shifting manually in triptronic mode as it should each time you move the shifter lever, and if the PRNDS is lit up, then iirc the paddles don't work, and possibly getting stuck until you move the shifter to park, and restart the engine, just a thought.

Do your symptoms change between auto drive mode, sport mode, or triptronic manual mode, and or using the paddles in any mode ?

When you had the "values reset", did anyone perform the proper driving procedure of gentle acceleration to speed, and coasting down to almost a stop, iirc, this is to be performed 6 times, at least according to other brand's tsb's.

I will add that the ZF 6HP-26 transmission does have it's issue in certain brands, "Hooting between 3-4" in some D3 Audi A8L/W12, "seal leaks" in the BMW, Jag, and Aston DB9, but I really can not recall anyone here ever having these issues with the Bentley, the Audi did a fluid upgrade, along with a software flash to the transmission control module for its 3-4 hoot issue, and I can say that my 2005 A8L W12 with the ZF 6HP-26A has never had issues, and that is now at 200K miles, my GT has the Supersports ZF 6HP-28, so I can not comment on the characteristics of the 26 in the B.

If you do replace the solenoids, be sure to replace the seals as well.

Johnny

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Hi Johnny,
Thanks for detailed response. It's much appreciated.
I don't think it's the dust cover tbh. It's fully intact and seems fine.
The problem is the same, regardless of auto ,
Paddles, manual etc.
I do get some hooting when it happens so perhaps that helps with the diagnosis?
The indie specialist reset the values electronically, not through road testing etc.
I did read somewhere another owner had similar issue and replaced the power lead to the valve body. Maybe I could try this too?
once again thanks for your comments.

 

Hello, żDid you ever fix tour issues with your transmission?

 

Hi
Yes. It was Solenoids in mechatronic. £1500 fix.