just changed my final drive oil and guess what

[autogs]

no slivers of metal or filings of any sort,drive shaft uj in clean condition too,
no sign of water in the shaft housing either

so perhaps ive got a good diff assembly and wont have any probs

 

[mechcanico lee]

Good news for you sir How old is your bike and how many miles it done out of interest....and is this the first time the diff oil has been changed ?

 

[autogs]

its a early 08 but an ex offroad school bike so i was expecting worse,done 12000 miles now,not sure if it has been changed,did not look like it had been dropped down before,but a lot of dealers seem to suck the oil out rather than drop the fd down and let it drain properly so thats why i did it this morning

 

[Davy F]

I changed my diff oil at 12k, then 24k. Clean as the proverbial whistle. But man does that oil stink !!

 

[autogs]

sfunny i cid not notice the smell but the other half came into the garage to put some washing on and started ranting about a rancid pong and promply left,(the garage not me)

 

[GrinningGSer]

changed mine at 6K and again 11K ( been in a few fords) and clean as a whistle and no nasty smells and no pinion shaft play. Probably no need to do this, but I do worry

 

[mechcanico lee]

A have always wondered why the diff units fail on the 1200 a little more than you would expect, maybe the ones you see reported on here havent had oil changes but dought it as most folk on here seem intensive with there maintanence, and i have read some reports that they have had new diff units replaced and 10k down the road they fail again.
Is it poor build up at the factory, or poor grade bearings or materials i just dont know, but you would think that a diff unit would last the life of the bike.

Perhaps Bmw should get Honda to make the diff unit .

 

[cookie]

um, they're not diffs

 

[Padge]

no slivers of metal or filings of any sort,drive shaft uj in clean condition too,
no sign of water in the shaft housing either

Me too....yet I still had to rebuild with all bearings and seals
Seems that some with filings and metal go on to have a long life yet some with clean (but smelly) oil don't.

Bad design and incorrect shimming during assembly are my thoughts.

 

[ktmmark]

My money is on the build up @ the factory, as with the 1100/1150 my mate's had 6 fail in 50,000 mile 5 replaced by bmw dealers. After the last one failed we replaced the whole drive unit problem sorted.
My 1100 on the other hand is still origional apart from the seal @103,000 mile.

 

[Spout]

Seems that some with filings and metal go on to have a long life yet some with clean (but smelly) oil don't.

Bad design and incorrect shimming during assembly are my thoughts.

...and of course the main bearing is a seperate sealed unit, it's condition and the oils condition are not linked.

 

[RickG]

...and of course the main bearing is a seperate sealed unit, it's condition and the oils condition are not linked.

It's not sealed.

If the oil comes out black (except for the first change) and exceptionally smelly it can indicate one or more bearings is failing

 

[autogs]

um, they're not diffs

yes your right of course,

although with a pinion and crown wheel you can see the similarity,fd or angle drive?

so is the bearing sealed or not,dont want to start an argument just interested like

 

[mechcanico lee]

um, they're not diffs

Sorry i stand corrected , final drive unit then

 

[RickG]

so is the bearing sealed or not,dont want to start an argument just interested like

There are 4 bearings, two support the pinion shaft, two support the crown wheel. Only one bearing is sealed which is the LHS crown wheel bearing, the one nearest the brake disk.