This can't be good.

[bemiiten]

My biggest fear was to go through all this and not be able to detect a bad bearing. All the rear bearings are turning smoothly and seem fine.

I start heating the front case.

And heat some more. and some more. It shows 205 but my hands are to oily to grab the camera.

Around 220 degrees the input and output shaft bearings are moving easy ready to drop out. The intermediate shaft will not budge. I go at it for a hour and a half with temps up around 230 with no luck. I'm getting frustrated so this round is lost.

Chinese takeout intermission.

[bemiiten]

At dinner my fortune cookie reads , "If you don't fail now and again, it's a sign that your playing it safe"

I consider my options

1. Put the trans in the oven and bake until the shafts come out, or clouds of smoking gear oil attract the fire company.
2. Make up a jig and pull it out while hot.
3. Give the heat guns another try.

I concentrate all the heat on the intermediate shaft. 260 degrees and still no give. I support the intermediate shaft by holding it in one hand with a set of gear puller jaws. I elevate the entire assembly off the bench and ,not wanting to play it too safe , give the back of the bell housing a few whacks with a rubber mallet. Finally it relents after a dozen or so soft blows.

I am relieved to see the intermediate bearing clearly looks and feels completely buggered. No doubt , This is the culprit!

All three front bearings show signs of disscoloration , but only the intermediate feels bad.

[osii]

will you come to my house and fix my GS?

[bemiiten]

Output shaft.

Input shaft

[bemiiten]

Originally Posted by osii

will you come to my house and fix my GS?

California No problemo, I'm on a plane. Now I may need to take it for a test ride afterwards!

[Mr. Magoo]

I would like to have your wrenching skills. Good luck!

[Komet]

Originally Posted by Rub'erdown

I would like to have your wrenching skills. Good luck!

Concur.

[kdude]

Oh Man.. What an exciting post ! Can't wait to see how it all turns out. good luck.

[dannyleo]

Just a guess, input shaft bearing. Had exactly the same type of description as what you gave and that's what they found on pulling it apart. It felt just a shade unsmooth until you pushed on it at the same time as turning it, then it was downright gritty. Be interesting to hear how it turns out.

[bemiiten]

Here is a pic of the metallic fuzz on the black magnetic drain plug found at the bottom of the transmission. When I discovered the problem , first thing I did was to remove the fill plug to inspect the oil level. It was fine. Next I drained the gear oil into a clean pan to check for debris with a magnet. There was a little bit , but the small amount of fine metal particles in the hot oil would give me little concern normally.

I never removed the black magnetic drain plug on the bottom of the trans before because the cat. needed to come off to gain access. I found a short 3/8 bolt that has a 9/16 hex fit's perfectly. I put on two nuts and used a wrench to remove the plug with the exhaust in place.

I would soon find out that despite the service manual making no reference to remove and clean this plug for normal maintenance, not doing so was a major blunder on my part. The plug was absolutely filled with super fine metallic fuzz. I cleaned it up , refilled the trans and decided to take the bike for one last ride around the block to listen to the grinding noise one more time and to shoot the video. I should mention I drained the final drive just to make sure That the noise wasn't being transmitted somehow to the trans. Nothing at all was found on the drain plug.

Here is a picture after I cleaned the trans plug once already. I rode the bike less than a mile and managed to pic up this much more debris!!!

You can bet that this will be coming out at every service from now on!

[bemiiten]

This is what was recommended by the dealer. I normally use what is called for in the manual. I already was using the 75/140 before I discovered the fact that it calls for 90w. This issue has been debated here before.

Over the years , The container has been changed but what came out looked the same. BMW's latest lubricant is now red in color where the old stuff was the normal gold/brown color.

Being the anal type, this set off alarm bells at my last fluid change. 5,000 miles later , bearing failure.

So I'm left wandering why shit happens. So what do you think?

• • The fuzz in the oil found it's way into the bearing and destroyed it.
  • The large amount of fuzz is from the bearing failure
  • The bearing was improperly shimmed at the factory, but took 55k to fail.
  • The catalytic converter's excess heat played a role in cooking the bearings.
  • Changing to the red oil did it!!!
  • The case is improperly machined , hence the reason the bearing would not come out while all the rest were falling out at a much lower temp.
  • Shit happens

[JimVonBaden]

Just a few of my opinions:

The fuzz isn't a concern unless it had very descernable chunks, or flakes of metal on it. Notmal wear and tear, along with break-in will create very small fuzzy particles that nicely stick to the magnetic pick-up.

The different color of your oils mean nothing. They have different colors so I wouldn't worry about that.

I would bet that it was just your time. It seems like you did all the correct maintenance, so I wouldn't blame yourself.

Jim

[blackbirdzach]

Originally Posted by bemiiten

California No problemo, I'm on a plane. Now I may need to take it for a test ride afterwards!

I'm very impressed. I wish I had the tools and knowledge to work on my own stuff.

[SQD8R]

Hey Bemiiten,

Nothing to add other than appreciation for the time you are taking to show us your progress.

Dale

[bacon]

Hey Bemiiten

When you made the vary first post I almost spoke up to tell you what I thought it might be. Well I have been following this and I am so glad I did not say anything to show how stupid I am. You are so far advanced in your ability I don't have a chance. If I get my valves set and TB's set I think I did some thing. Well thanks for taking your time and making us all feel so small.
Thanks for a great thread
Tim