Auto & Diff Fluid Changes

[cj10jeeper]

I'm running a systematic refresh of many parts that may be considered as coming towards end of lifetime as I pass 80k. Today was read axle oil and auto box.

No 'How To' as Shipkeller wrote these some years ago and they are spot on.

Diff was surprisingly quick and easy and actually the oil came out looking like new, so probably little benefit in that.

Auto box was a little more surprising. Oil came out looking like tar as per sample. New was colour of weak tea... Thankfully box had no metallic bits in it, so glad I did this task. Filter change, awkward filling, running engine and topping up,all went well.

Results were astounding. The box is now so smooth. Had never appreciated how harsh it had become with rough and somewhat snatched changes. Glad I did it and highly recommend so doing do £70 of oil & £15 of filter & seal (plus £10 for diff)

 

[pvr]

Is this a "sealed for life" type gearbox? I remember when I had a sump leak on my previous X5 that when they changed the oil in the gearbox (sealed for life), that I lost the lurch it had when slowing down to a stop. Certainly worth doing I would say.

 

[cj10jeeper]

Yes Pvr - lifetime oil, but in reality BMW consider that to be 100k, so a good investment after 12 years and 80k

 

[firebobby]

Where do you fill the gear box from and is there a link to doing this work.
Thanks

 

[cj10jeeper]

It has a fill plug on the rear left hand corner. Needs a pump and flexible hose to access it.

There's a detailed 'how to' on the forum authored by former ember Shipkiller

 

[GuidoK]

Was this a complete flush (so about 10-12L of atf) or just a drain&fill
If the fluid comes out looking like that maybe an extra flush is needed?
It's very black...

Auto transmission specialists mostly have a special machine that flushes the complete system, so including the torque converter and heat exchanger.

 

[cj10jeeper]

No I opted to do a warm up, drain, pan off filter change and refill.

There were no visible deposits anywhere other than base of the pan and no burnt oil smell.

I'll sample it in a month and see what I have, but no concerns.

 

[Zed Five]

+ 1 on refreshing the auto fluid. Had my wife's Golf done at 60k. It transformed the car. Super smooth changes again. Definitely worth people doing this at these sort of mileages.

 

[ranski]

The past year the gear changes have felt somewhat jerky and not smooth compared to previous years. So I dropped off the Z before I went on holiday and picked it up this morning from its automatic gearbox oil change. (12 years old with 78k on the clock)

There's always the placebo effect on changes such as this, but from the 80 miles I covered today, mostly urban. The gearing appears to be smoother and less jerky, especially in non sport mode.

 

[Scooba_Steve]

Having felt the difference doing it on a manual I can imagine how much it would affect an auto. Well worth doing though not that cheap with so much oil in the auto. I will be aiming for 30k changes from now on.
Diff also seemed OK on mine but was pretty discoloured, not as bad as the box, but worth doing for the £15 and 2 plugs it cost.
Nothing metallic found in mine either which is a testament to good engineering but the colour and consistency of what came out was horrible.
I'd advise everyone to do it - especially those low milers