trans & FD oils and crush washers

[shake1150]

I'd like to change the transmission and final drives fluids on my R...

two questions:

1. which gear oil do I buy? there's the BMW synthetic 75W-140 gear oil and the BMW 80W-90 Hypoid gear oil. I know there's other manufacturers of the same stuff (castrol, mobil 1 etc). which one do I use? the 75W-140 for the transmission (for higher heat caused by the cat) and the 80W-90 for final drive? or put the same stuff in both the transmission & final drive? all recommendations are welcome.

2. Is there a crush washer for the transmission drain plug? I can find the part number for the transmission fill plug and not the drain plug (from the microfiche at ascycles.com)... my dealer says its not required... if there is one that is used, then anyone have a part number? or is it the same as the crush washer as the fill plug?

thanks!
d

[challey]

This is a topic that comes up repeatedly - if you search, I'm sure you'll find some lengthy discussions about it.

That said, the simple answer about the fluid weight is: Use what is recommended in the owner's manual." For the brand, the simple answer is: Feel free to use any high-quality lube from a reputable manufacturer."

I don't have access to my owners manual but I don't think you can go wrong with 75W-140 for the transmission. My choice was Red Line synthetic but there are any number of other suppliers that you could use. For the final drive, 80W-90 should be fine. Several very knowlegable BMW service types have told me that synthetic is not necessary for the FD and should not be used. This recommendation was based on their years of working on BMWs - there does not appear to be any testing data confirming it however. One guy - they owner of a well-regarded independent BMW shop - went further and told me that in his years, he had never seen a FD failure in any bike using Castrol Hypoy C gear lube (a conventional lube). I switched to the Castrol from Red Line synth figuring that I had nothing to loose.

On the trans drain plug crush washer, I seem to recall that there wasn't one which seemed strange, since the fill plug had one.

Charlie
"There is no exception to the rule that every rule has an exception." -- James Thurber

[Phang]

I changed mine last week, Redline Shockproof Heavy in the transmission and Mobil 1 SHC 75W90 in the FD.

The drain plug of the transmission has the same crush washer as the filler plug. Measuring 22mm X 18mm (part number 07119963300) and torque to 30NM for both plugs.

Cheers,
Phang

[Buckster]

You will get a lot of answers on the oil. I use sythetic in both. Most do not. I also use 10% Guard Dog moly in both.
I have used the same crush washers at least two different fluid changes. Just inspect before re-use.

[twindave]

+1 on the guard dog moly. Shifts like butter!