[TurboWeasel]

Just changed mine out with the genuine G1 oil from BMW. 66K miles. It came out Golden Syrup coloured, so pretty dark compared to fresh fluid, which is Sunflower oil in colour (and viscosity!).

The diff wasn't noisy. Just proactive maintenance.

Literally took 30 mins, including jacking the car up.

Dry capacity is 1.5 litres according to RealOEM but most people report only being able to extract 1-1.2 litres, which is what I found also. Still, 66% fresh is better than 100% old and rotten.

There is no drain plug, so it's a suction method. A U shaped pipe helps get the oil out of the deepest part of the diff.

Anyway, just thought I'd pass that on as it's very easy now that the weather has improved. The only downside is the BMW oil is expensive!

[danb1979]

Originally Posted by TurboWeasel

Just changed mine out with the genuine G1 oil from BMW. 66K miles. It came out Golden Syrup coloured, so pretty dark compared to fresh fluid, which is Sunflower oil in colour (and viscosity!).

The diff wasn't noisy. Just proactive maintenance.

Literally took 30 mins, including jacking the car up.

Dry capacity is 1.5 litres according to RealOEM but most people report only being able to extract 1-1.2 litres, which is what I found also. Still, 66% fresh is better than 100% old and rotten.

There is no drain plug, so it's a suction method. A U shaped pipe helps get the oil out of the deepest part of the diff.

Anyway, just thought I'd pass that on as it's very easy now that the weather has improved. The only downside is the BMW oil is expensive!

I've got this:

https://www.amazon.co.uk/Sealey-AK54...s%2C111&sr=8-4

Warmed the pipe up in some boiling water to put bit of a bend into it to begin with and it works brilliantly

I've yet to do mine; body's not going to let me crawl under the car any time soon so I'll get it done on my pals ramps next time I remember it

Already have the oil in from my F01 and a spare brand new OEM diff plug

https://www.ebay.co.uk/itm/174108592...Bk9SR_7usajsYw

However it's here on Listers BMW eBay: https://www.ebay.co.uk/itm/285209080...Bk9SR4qGxqjsYw

That's using RealOEM for the PN

But BMW eBay have it here and compatible with F3X with 10% off

https://www.ebay.co.uk/itm/186276806...3ABFBMtM68qOxj

Weird! Different PN too

It should be 75W85 IIRC

My pal's used this with ZERO issues:

https://www.ebay.co.uk/itm/173578367...Bk9SR4yGxqjsYw

BIG price difference!

[TurboWeasel]

That's the same syringe I used, works perfectly

Yeah it is odd there's different part numbers for the oil. I just went with what RealOEM specified for my 30d, which is the funny little 0.5 litre bottles.

I didn't bother changing the fill plug in the end as I don't want the warranty company knowing I'd been in there I got a pair of them from Listers for a tenner

Yeah the Febi stuff will work, as will other 75W85 oils, but I just played it safe with the OEM stuff

[Allworth]

I've used Febi oil, no issues. Just need to make sure it matches or exceeds GL index in this particular case.

[dholdi2]

I used the LiquiMoly oils for both diffs when changing mine.
I dont think there's much to choose between any of the reputable brands.
The main thing is to get it changed and not believe this sealed for life bs.

[TurboWeasel]

Yeah there is no service interval on the rear diff. But BMW will happily sell you gear oil and a drain plug

Deep down BMW know guys like us exist, hence why there is still plenty of parts available for the E30. Try getting parts for Golfs and Corrados of the same era! The 'sealed for life' nonsense is for average schmoes.

I used to use Redline gear oils back in the day. Their MTL absolutely transformed clunky old recalcitrant VW gearboxes, but until 100K where I ditch BMW completely, I'm keeping her all OEM