What type of final drive and transmission oil to use??

[Bubbadozer]

TI apologize in advance, as I have no owners manual or anything regarding this bike. I am wondering what types of oil to use for the final drive and transmission.

 

I CASTROL AXLE LIMITED SLIP 80W-90 gear oil that's API GL-5 rated. Will that work? I have some leftover Gear 300 by Motul from another bike, but only about 480cc's worth. I have plenty of the Castrol, but was wondering if that would work for both.

 

Thanks for all the help. This newbie appreciates it;).

Edited June 29, 2017 by Bubbadozer

[dirtrider]

TI apologize in advance, as I have no owners manual or anything regarding this bike. I am wondering what types of oil to use for the final drive and transmission.

 

I CASTROL AXLE LIMITED SLIP 80W-90 gear oil that's API GL-5 rated. Will that work? I have some leftover Gear 300 by Motul from another bike, but only about 480cc's worth. I have plenty of the Castrol, but was wondering if that would work for both.

 

Thanks for all the help. This newbie appreciates it;).

 

Afternoon Scott

 

You could use that 80w90LS GL-5 gear oil but it isn't the best choice. Personally I would use a non LS gear oil. About any quality 80w90 Non LS GL-5 rated gear oil will work as well a 75w90 GL-5 non LS synthetic.

 

You are probably better off using a conventional 80w90 GL-5 non LS as that gear oil usually has more seal conditioner in it so is less likely to seep past the pinion seal (the BMW 1100/1150 bikes are kind of known to have some pinion seal seepage)

 

On the transmission, I definitely don't recommend a LS (limited Slip) gear oil. That same 80w90 GL-5 will work but most use a synthetic 75w90 or 75w140. Cold weather shifting will be better with the 75w90 gear oil. Some transmissions shift better with the 80w90, some shift better with the 75w90, & some shift better with the 75w140 (about all you can do is try them until you find what your bike likes best)

 

[Bubbadozer]

How about a mix like half and half of synthetic 75w-90 and non synthetic 80w-90 oil in the transmission?

[Michaelr11]

 

I CASTROL AXLE LIMITED SLIP 80W-90 gear oil that's API GL-5 rated. Will that work? I have some leftover Gear 300 by Motul from another bike, but only about 480cc's worth. I have plenty of the Castrol, but was wondering if that would work for both.

 

Yes, the Castrol 80W-90 will work for both. Castrol changed the name a year or two ago, the same product used to be Gear Oil. A very well respected BMW mechanic, independent shop in PA, rebuilds transmissions all year, sends his rebuilds back with the recommendation to use the Castrol 80w-90.

[Bubbadozer]

But what about the limited slip, as dirtrider stated, that the LS wasn't recommended in the final drive and gearbox..

 

Thanks guys.

[dirtrider]

How about a mix like half and half of synthetic 75w-90 and non synthetic 80w-90 oil in the transmission?

 

Morning Bubbadozer

 

Never a good idea to mix oils unless you are stuck & have to do it. In most cases it causes no harm but there is no guarantee that the additive package in one oil will do it's intended job when mixed with different additives from another oil type. Plus, as a rule, 80w90 is a conventional gear oil & most 75w90 gear oils are synthetic. While they probably they could be mixed I doubt that you will find any oil company that would recommend it.