BW8 replacement oilseal manual control shaft assembly


Does some one knows how to remove the manual control shaft assembly (nr. 12) in a automatic transmission unit? It is a BW8 AS4 8G unit (E-type 2+2 1970). I want to replace the oil seal (nr. 6) of this selector shaft. Is it possible to remove this with the transmission unit in the car?



Hi Harrie.
It’s unlikely that you can do it in the car, and it is far easier to do the work on the bench; the detent ball is the worst part of it but the work itself is not so bad.
I don’t think you can drop the transmission far enough with the reaction plate in the way but it is worth a try. That way or by also lowering that you could leave the engine in the car and have enough space to remove the shaft. It’s not the best design to say the least, on an otherwise good transmission. You have to pull the selector shaft out all the way.

Hi David,

In principle there is room to remove the shaft from the driver side inside the car. See picture below.

The oil seal is unfortunately inside behind the metal. I would like to know what is needed to remove this shaft.


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That’s perfect! Didn’t know the access plate was this convenient. Bad pictures follow shortly

This is what I took out to exchange the seal
The adjustment linkage is on the left, it will be obvious, it is not too difficult if you have the manual. With one exception: The detent is made by a spring loaded ball bearing ball that is a bit difficult to insert. I believe I used a length of tubing to hold it in place on reassembly and lost the ball a few times. The rest was easy, doing it upside down is annoying, oil will keep dripping for hours. The rest is much easier than it looks! just a few tubes and bolts and nothing can go wrong when you have a clean workbench.

The transmission is dry now. I also adjusted the band that is done from the inside.

This is everything back together. As you can almost see the shaft just pulls out once the nut on the inside has been loosened. If the disc on the outside was a simple washer this would be a very easy job.

Hi David,

Thanks for your reply.
I have 3 additional questions if you don’t mind.

  • I ordered the selector shaft oil seal. It seems symmetrical. This means it doesn’t matter how it is placed? No front or back side?

  • Adjusting the band from inside. Can you explain that how to do? Because mine has to be adjusted as well

  • My kickdown isn’t working. Do you have an idea how to solve that?



[quote=“HG_E-type, post:6, topic:414465”]
I have 3 additional questions if you don’t mind.

  • I ordered the selector shaft oil seal. It seems symmetrical. This means it doesn’t matter how it is placed? No front or back side?
  1. As with all single lip seals, the lip should point inwards to stop the fluid coming out

  2. Band adjustment procedure is in the FSM

  3. Almost every BW8 will not kickdown, I ask every owner, on this forum and elsewhere
    I tried everything. An old Pro told me changing the valve body is the only cure
    (the valve body part num was changed several times throughout production)

there is an external pressure adjustment nut & procedure outlined in the FSM. I doubt it will work. I dismantled several BW8 valve bodies to understand this issue, and can find no reason, there is no defective parts or internal adjustment possible

You are lucky to have side access via a panel, on my 420G, this operation requires removal of the engine and gearbox

Doing the job upside down will be impossible unless you take this TIP…it is possible to insert the spring and detent ball with a simple trick…the lever must be “overclocked” just past its maximum position, and this will allow you to insert the spring and ball with a magnet, release the overclocked lever and they will be held in place

Hi Tony,

I don’t have the FSM. Do you have both parts (band- and kickdown-adjustment) in a pdf file?



As long as shift points are correct, nothing can be done. I believe I have had kickdown, but now the throttle rod has fallen apart again and I need to investigate. I think I like it without kickdown, I can always shift to low if I need more power.

You will want a few litres of atf to top up.
The adjustment is in the manual; not much torque.

If you don’t have a manual, they are incredibly helpful and a reprint is always with me in the car. I don’t have a pdf of it and can’t send you photos atm.