one for the anoraks regarding diff and gearbox oil a

[bigchap39]

want to change it but getting no where with bmw so spoke to my neighbour as his son is a bmw mechanic.Now he has said that all the 2.8 have a lsd.Mine is a 2.8 on a r plate.next query is,he got me the diff and the gearbox oil.Hes supplied me for the gearbox automatic transmission fluid,to be exact comma aqm mineral atf which he says it what it takes.now i used to be a mechanic 20 years ago and atf was always just used for an auto.Also hes supplied me with comma lsd ls80w-90 mineral gl-5.I have read up on a few threads on here and they say to use 75-140 for the lsd im sure.So the question is has he giving me alot of useless oil and if so what do i need to but and does my car have an lsd as this is driving me nuts as have drained it already and cant get her moving again till replaced.the gearbox has the yellow sticker with MTF-LT-1.
cheers for much need help

[zibomb]

Cant help you on the oil im afraid but I have a r plate 2.8 and that definitely has a lsd diff. hope it helps

[Del]

I became an anorak when I decided to change my gearbox and diff oil recently! The recommendation for the diff (on this forum and elsewhere) without a LSD, is fully synthetic 75W/90. My 1.9 fits this category and I used 1 litre of the Carlube brand from GSF. However, I noticed that on the container it stated that it could also be used for cars with a LSD??

The recommendation for Z3s with a LSD (both on this forum and by Castrol) is fully synthetic 75W/140. Castrol seem to play a dominant role in terms of choosing BMW lubricants which means they are either the leading experts or have very good marketing managers. My understanding is that the 2.8 has a LSD but you need to check your original vehicle specification to be sure. For the larger engine Z3s I’ve seen diff oil capacities of 1.25 – 1.75 litres mentioned on this forum.

Choosing the right diff oil was simple compared with getting the right gearbox oil! My local Bristol BMW main dealer told me it is essential to check the label near the gearbox filler plug. According to Castrol it seems you can have an orange label (ATF oil), green (special oil?), two variants of yellow (MTF-LT-1 or MTF-LT-2) or no label (I’m not sure what oil that requires). There is more information on this forum about this topic from Mike Fishwick. The 2.8 gearbox is different from the smaller engine 1.9s such as mine. Research I did, suggested that BMW kept changing the oil specification for the 2.8 gearbox as some customers in cooler parts of the world found the gear change a bit stiff – I don’t know if that’s totally true or not but I do know that ATF fluid is recommended for some of the gearboxes. I’ve also seen some of this forum say they just stick in 75W/90 and all works fine.

Clear (as mud) now?

[Del]

Here's the link I mentioned http://zroadster.org/wiki/general-maint ... -fishwick/

[bigchap39]

cheers for that but it still doesnt say for defo that the atf can be used as could end up expensive mistake.

[Mike Fishwick]

If you look at the gearbox filler plug, you will probably see it has an orange label telling you to fill with ATF - not that it is important, as the gearbox is the same as on a 1999 model which has a yellow 'Lifetime' oil sticker, which really means a synthetic 75-90 gear oil meeting GL4 or 5 spec. Lots of gearboxes use ATF, which is a decent oil, and is usually about SAE 85 on the gear oil scale - about the same as Amsoil MTF, which is widely used, so don't panic!

The older brown label meant it was filled with mineral oil, and as such boxes may have copper alloy components such as bronze selector forks, a GL4 oil only is appropriate - synthetic or normal.

[bigchap39]

ok so can use the atf he gave me for my gearbox which has the yellow sticker.Regarding the ls80w-90 diff oil he gave me can i use that or am i better to go buy 75w-140?

[Mike Fishwick]

As per my bit in the Knowledge base - check if your car has an LSD, by asking a dealer to print out the options list in response to your VIN code's last seven digits. It is listed as a Sperrdifferential 25%.

[c_w]

Re: the diff on the 2.8. If it does have an LSD then it's not critical to use the 75-140, this is mainly for the M Clutch type LSDs.

IF the 2.8 has an LSD it will be the torsen type which is mechanical and essentially lots of worm gears inside so other than the normal lubrication of the gears it should be fine on most oils. The 75-140 was developed to maintain the correct slip of the clutch plates in the M diffs and/or control noise. But any good diff oil will be fine in the Torsen type as they are maintenance free.