Final drive

[Pat]

Has anyone here rebuilt there final dive? If so -- is it as hard as the repair manuel makes it out to be?

[dshealey]

Has anyone here rebuilt there final dive? If so -- is it as hard as the repair manuel makes it out to be?

If the bearing pre-load is not measured and shimmed properly the chance of an early failure of the new bearing is greatly increased when the crown gear bearing is replaced. If gears or pinion bearings are replaced, then the added measurements to insure proper gear contact pattern are EXTREMELY important. If the small tapered roller on the crown gear shaft is replaced, then everything has to be measured/shimmed. Those who have re-built or had rebuilt drives done by just replacing the bearing without properly re-checking the pre-load should be riding with fingers crossed.

Yes, it is as difficult to do as the service manual shows if you want it done properly with reasonable chance of long term success.

My opinion is that few BMW dealerships will or can re-build one properly. Which ones? Who knows?

[JohnR]

I don't want to shoot down your theory about the importance of measuring everything, but when my local BMW shop rebuilt mine (at 97K), they just put in the new 17 -bearing thingy and bolted it down. When I sold it 30K later, there was no sign of metal flakes in the diff-oil when I changed it last. As far as I know, it is still going strong and the new owner rides it everyday to work and home (over 50 miles daily).

In fact, the cost to have the shop do the job for me was just a tad over $300, and the parts were the biggest portion of that, so my call is it ain't worth doing it myself, when they can do it pretty cheaply.

[dshealey]

I don't want to shoot down your theory about the importance of measuring everything, but when my local BMW shop rebuilt mine (at 97K), they just put in the new 17 -bearing thingy and bolted it down. When I sold it 30K later, there was no sign of metal flakes in the diff-oil when I changed it last. As far as I know, it is still going strong and the new owner rides it everyday to work and home (over 50 miles daily).

In fact, the cost to have the shop do the job for me was just a tad over $300, and the parts were the biggest portion of that, so my call is it ain't worth doing it myself, when they can do it pretty cheaply.

Who cares what one shop did? Was it done correctly? NO. Is there a chance that some quick re-builds without properly checking the measurements will survive? Yes. Will all of them done this way survive a long time? No. As witnessed here with some re-builds failing early.

Shortcutting a proper documented procedure is a big gamble, sometimes you win, sometimes you loose. Yours was one of the lucky ones. One in a row is not statistics.

[grifscoots]

One in a row is not statistics.

Is one in a row even a row?

[dshealey]

Is one in a row even a row?

It is either a row, or a column. :D

[McAllister]

It is either a row, or a column. :D

Only after the second sample.

Can't sleep David? It's what, 4:19 in the morning !!!

[clay]

I don't want to shoot down your theory about the importance of measuring everything, but when my local BMW shop rebuilt mine (at 97K), they just put in the new 17 -bearing thingy and bolted it down. When I sold it 30K later, there was no sign of metal flakes in the diff-oil when I changed it last. As far as I know, it is still going strong and the new owner rides it everyday to work and home (over 50 miles daily).

In fact, the cost to have the shop do the job for me was just a tad over $300, and the parts were the biggest portion of that, so my call is it ain't worth doing it myself, when they can do it pretty cheaply.

JohnR,
I think I ran into you on I-70 a couple of years ago, you were coming back from Key West with a guy on a Gold Wing. I was on an FJR, was that you? Anyway, I have to agree with DS on this. The final drive on my first LT went out and the local BMW shop, replaced the the big bearing, under warranty. 10,000 mi. later it went out again. The second time they replaced the whole drive with a new one under warranty. I sold the bike and have bought a second LT, No drive problems so far, but did have to replace the clutch and slave cylinder, under warranty.
I guess the moral of this story is don't let the warranty run out on your LT.

Clay Hirner
Spring Hill, KS.

[Moonshine]

I would find it almost impossible to have a final drive big ball bearing failure without the debris from that failing bearing not destroying all of the other bearings in the final drive. In my case the bearing did not fail to the point that you could hear anything or feel anything but only discovered it when I did my normal 6,000 mile lube change. At this point all of the pinion bearings and the small tapered roller bearing had been trashed. I was amazed that the gear set was still OK. I am now convinced that when there is a big ball bearing failure and you change only the ball bearing without removing the final drive assembly and do not change the other bearings you are set up for another failure in the near future. When these ball bearings do fail they produce a lot of debris and that will be circulated through all of the other bearings along with the lube.

[JohnR]

JohnR,
I think I ran into you on I-70 a couple of years ago, you were coming back from Key West with a guy on a Gold Wing. I was on an FJR, was that you? Anyway, I have to agree with DS on this. The final drive on my first LT went out and the local BMW shop, replaced the the big bearing, under warranty. 10,000 mi. later it went out again. The second time they replaced the whole drive with a new one under warranty. I sold the bike and have bought a second LT, No drive problems so far, but did have to replace the clutch and slave cylinder, under warranty.
I guess the moral of this story is don't let the warranty run out on your LT.

Clay Hirner
Spring Hill, KS.
Hey Clay:

I do remember you at the gas stop in Missouri, and your story about LT problems. Guess I was just lucky with my old 2000 LT.

Glad your back with the LT. Assume you got a new one.

I traded up to a Black 2003 LTE this past year and am loving the intercom, GPS, FRS/CB and all, but the best upgrade on the 03 is the power-assist, linked brakes. Takes some getting used to it, but definitely stops quicker.

Give me a buzz (by PM) when you want to ride.

John R