Autobox oil change
QI have 2007 BMW Z4 E85 3.0Si with 52,000 on the clock. I am thinking it would be a good idea to change the gearbox (6-speed auto) oil and filter and the back-axle oil.
Could you give me a quick run-down on what I need to do to achieve this please? And would you recommend doing this?
I haven’t seen too many articles on maintaining these vehicles – but they are now at a price point where they are becoming affordable so it would be useful to have some information on tasks such as these. There is no Haynes manual that I can find for the Z4 so am left with googling for help.
Andy Harrington
AFirst, I will say yes, it would be a good idea to replace the gearbox and rear diff oil even though BMW describe both as lifetime lubricant, as this has probably not previously been done.
According to the data I have on your BMW you should have the 6-speed ZF gearbox fitted, the drain and refill plugs are both at the bottom of the gearbox, the drain is of course in the base of the sump and the fill bung is just above the sump in the same area but in the gearbox casing. Both according to the data I have require an 8mm Allen key to remove and replace.
The full capacity of the gearbox is 8.9 litres, but the drain and refill process should take around 4 litres – it is often recommended to do this twice to help remove as much as the oil fluid as possible.
The process is as follows:
Place the gear selector lever in ‘P’ and ensure the gearbox oil temperature is below 30°C.
▶ Drain the gearbox oil and replace the drain bung, then fill transmission with specified amount until fluid drips from level/fill hole.
▶ Fit the level plug hand tight and start the engine and allowing it to idle.
Then select each gear several times, then return selector lever to ‘P’.
▶ The engine should be run until the gearbox oil temperature is 3050°C, this should be checked using diagnostic equipment but running temperature can be assumed.
▶ With the engine still running check the gearbox oil level. If no fluid loss is apparent: Then top up until fluid drips from level hole. Re-fit and tighten level plug.
The rear axle may not be fitted with a drain plug as not all were. If it does have a drain plug then the process is quite simple and requires the oil draining down and then refilling using the filler plug in the diff casing.
The recommendation I have for the rear diff oil is: BMW Synthetic OSP (75W-90) – BMW part No. 83-22-2-365-987.
The recommend lubricant for the gearbox is: Shell M-1375,4 BMW part No. 83-22-0-142-516. sequence. If the driving cycle does not allow this to take place, then it will try again when the engine has reached the correct temperature, as yours has done. If you cannot fulfil the driving requirements to regenerate the DPF, it would be advisable to allow a garage with the required diagnostic equipment to carry out a forced regeneration before the DPF gets too blocked.