Automatic gearbox maintenance

[Zedebee]

Hi all,
I’m thinking of changing the transmission fluid in my autobox. They are supposed to be sealed for life, but probably not designed for 20 years. What benefits can I expect and what downsides might there be?

(And please no bollocks about getting a manual. I’ve had three manual Z4s and the auto is my preference ).

 

[bigwinn]

Hi matey

I always change the auto box fluid

Buy 6-7 litres of fluid and a filter. Pop the drain and fill plug then drop the sump. Clean the magnets in the tray. New filter is usually held on by one screw. New gasket back on.

Fill it in until it starts to overflow- prob 4 litres.

Then with all 4 wheels off the ground start the car, put it in each gear slowly. Let it run in D on tickover and refill it until it overflows again

The liquid that comes out will have the consistency of tea. It’s awful.

Deffo expect smoother quieter changes.

The stories about changing the fluid causing issues- it’s never manifested. Sealed for life I understand is because the box is expected to last 100k… so that’s the lifetime

I look at it that I wouldn’t hesitate changing manual gearbox fluid so why would auto be different

Hope that helps

 

[MeinMotorradsZ4]

Hi matey

I always change the auto box fluid

Buy 6-7 litres of fluid and a filter. Pop the drain and fill plug then drop the sump. Clean the magnets in the tray. New filter is usually held on by one screw. New gasket back on.

Fill it in until it starts to overflow- prob 4 litres.

Then with all 4 wheels off the ground start the car, put it in each gear slowly. Let it run in D on tickover and refill it until it overflows again

The liquid that comes out will have the consistency of tea. It’s awful.

Deffo expect smoother quieter changes.

The stories about changing the fluid causing issues- it’s never manifested. Sealed for life I understand is because the box is expected to last 100k… so that’s the lifetime

I look at it that I wouldn’t hesitate changing manual gearbox fluid so why would auto be different

Hope that helps

Good info, wanting to do this too before it gets too cold.

 

[Zedebee]

Hi matey

I always change the auto box fluid

Buy 6-7 litres of fluid and a filter. Pop the drain and fill plug then drop the sump. Clean the magnets in the tray. New filter is usually held on by one screw. New gasket back on.

Fill it in until it starts to overflow- prob 4 litres.

Then with all 4 wheels off the ground start the car, put it in each gear slowly. Let it run in D on tickover and refill it until it overflows again

The liquid that comes out will have the consistency of tea. It’s awful.

Deffo expect smoother quieter changes.

The stories about changing the fluid causing issues- it’s never manifested. Sealed for life I understand is because the box is expected to last 100k… so that’s the lifetime

I look at it that I wouldn’t hesitate changing manual gearbox fluid so why would auto be different

Hope that helps

Cheers Biggie, I’ll give it a go.

 

[Rockhopper]

My local auto box specialist refused to touch mine because as far as we knew it’d never had a fluid change. He said if it’d been done a few times before then he’d do it but as it is, leave well alone.
Also there is about two litres of fluid in the torque converter that you won’t be able to get out.

 

[kis]

My local auto box specialist refused to touch mine because as far as we knew it’d never had a fluid change. He said if it’d been done a few times before then he’d do it but as it is, leave well alone.
Also there is about two litres of fluid in the torque converter that you won’t be able to get out.

I've had mine done twice now. Was a bit unsure as 1st time I just used an Indie, which I now no longer trust. Been taking my fleet to RBM for a few years now. Fluid looked golden, so nice and clean. So any fluid 'stuck' would be greatly diluted now

 

[B21]

ZF own recommendations who make most BMW fitted auto boxes state 50k-65k miles per change..

But what do they know ?

BMWs service regime is to minimise cost of servicing during the warranty period..hence why they bin it..along with with their 25mph-30k mile oil changes