Are any special BMW tools needed to replace the Thrust Bearing in the front of the gearbox. Or can it be extracted relatively easily and removed with any puller?
Thanks for your advice.
Thanks for your advice.
Thrust Bearing question 4 speed trans
- Thread starter Mal CSL 3.0
- Start date
Swallow your pride and call a Kiwi?
Pete‘s Gear Shop
(510) 537-9446
Pete‘s Gear Shop
(510) 537-9446
Which bearing are you referring to as "the Thrust Bearing in the front of the gearbox"?
The 6306 ball bearing that supports the input shaft?
Yes i think so. The symptoms are it’s a bit noisy but only when in neutral.
The blue manuals recommend a RILLEX 6306 bearing puller.
I use a German KUKKO 70-series puller (below) for the 6306 ball bearings on early Porsche rear axles.
A 6306 bearing is pictured on the tool.
I haven't used it on a BMW transmission, but I suspect it should work equally well... Don?
I use a German KUKKO 70-series puller (below) for the 6306 ball bearings on early Porsche rear axles.
A 6306 bearing is pictured on the tool.
I haven't used it on a BMW transmission, but I suspect it should work equally well... Don?
our shop has never repaired a 4 speed tranny.
We have 5 on the shelf just sitting. Literally not much of a market since so many people want 5 speeds, the 4 speeds just pile up on the rack.
Think preload when you have gear rollover noise. Not enough tension on the counter gear set. Very common. M3 Tranny’s came with a tensioner I think and Metric Mechanic went with Timkin bearings to help with the noise.
Try heavier oil and a smoother idle for best and cheapest results.
We have 5 on the shelf just sitting. Literally not much of a market since so many people want 5 speeds, the 4 speeds just pile up on the rack.
Think preload when you have gear rollover noise. Not enough tension on the counter gear set. Very common. M3 Tranny’s came with a tensioner I think and Metric Mechanic went with Timkin bearings to help with the noise.
Try heavier oil and a smoother idle for best and cheapest results.
You only asked about removing the bearing.
There's also a procedure, and a device, to re-install it on the input shaft.
My ZF 4 speed has a similar noise. I looked at getting bearings for the input shaft and found some of the needle bearings are NLA. I did find a RILLEX 6306 bearing puller but it's just gathering dust.
When I looked a few years ago, BMW dealers actually listed rebuilt 4-speed ZF transmissions for just over $3K, not that anyone is buying them since most want a 5-speed. Luckily, I picked up a rebuilt Getrag 5-speed for a good price so I won't have to worry about the noisy 4-speed once I swap them.
When I looked a few years ago, BMW dealers actually listed rebuilt 4-speed ZF transmissions for just over $3K, not that anyone is buying them since most want a 5-speed. Luckily, I picked up a rebuilt Getrag 5-speed for a good price so I won't have to worry about the noisy 4-speed once I swap them.
Below are the bearings I am referring to (1 and 5) that my mechanic calls "Thrust Bearings". And he asked me to check if any special BMW tools are needed to remove. Sorry if I wasn't clear before.
From my investigations, these are the two bearings that cause the transmission noise issues when not in gear, ie stationary at traffic lights in neutral.
I will buy part 1 below which is available at W&N, but seems part 5 for pre 73 CSLs with 4 speed is NLA. Anyone know where to get part 5? or is this unimportant to replace? (RealOEM dont even list the part number for part 5 for some reason)
From my investigations, these are the two bearings that cause the transmission noise issues when not in gear, ie stationary at traffic lights in neutral.
I will buy part 1 below which is available at W&N, but seems part 5 for pre 73 CSLs with 4 speed is NLA. Anyone know where to get part 5? or is this unimportant to replace? (RealOEM dont even list the part number for part 5 for some reason)
Mal, those are clutch release bearings. One is part of your clutch system.
It will not cause transmission noise, but might create noise itself when engaged, i.e. when you depress the clutch pedal.
Does the noise only occur when the clutch pedal is depressed?
Yes the increased noise happens when idling and also if clutch is drepressed. I will post up a video next time I have a drive.
Mal, I asked if the noise occurs ONLY when the clutch pedal is depressed... not "also" when.
If the noise occurs when the clutch pedal is NOT depressed, then the noise is not being caused by the items you posted images of...
Don’t overlook the pilot bearing which is sitting in the end of the crankshaft, also a source of noise.
The pic shows two throw out bearings as the 74 MY has the newer clutch slave and release arm. Part 5 is 74 and on, 21 51 1 204 419.
I can't speak to these (Getrag) transmissions specifically, but I have had other cars where the throw out bearing (parts 1 and/or 5) definitely made (an annoying, rattling) noise when idling (like at a stop light and you are not in gear, and you are also not depressing the clutch. For me, it typically goes away as soon as you depress the clutch and load the bearing. It probably also makes the noise when driving, but you can't hear it over the rest of the car-in-motion noises.
Stephen, other cars often have different clutch arrangements. Some have the bearings attached to the clutch plate, and are always in motion with the engine running. For now, Mal has indicated that the noise does not go away when the clutch pedal is depressed, as your noise did.
Mal has now identified the bearing that his mechanic wishes to replace- the clutch bearing, and not a trans or gearbox bearing- although the issue is still being described as "transmission noise". More detailed information on when the noise does or does not occur would be helpful to diagnose the issue...
This seems like a possible cause of the noise I've heard in mine. Or maybe not.
For what it's worth, here's the link to the sound I recorded.
E9 Clutch related noise - mulberryworks.mp3
drive.google.com
I recorded this shortly after I got my car on the road. At the time I thought it could be a throw-out bearing noise, but that seems less likely now.
You can hear the noise stop and start as I cycle the clutch pedal. There's a big hole in the passenger's floor so a lot of engine sound bounces off the pavement into the car.
Ultimately, the source of my sound isn't critical as I'm on the path to change from the 4-speed ZF to a 5-speed Getrag. I posted here more as an example of what kind of noises might fit the OP's issue.
In reference to the "Getrag rattle" I've heard about, it seems that it's something to do with loose (worn?) shift forks and can be annoying at idle. A friend had an early 7 series with it and it's a different sort of noise than what I've got.
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Roger that. Good info - sorry to have made assumptions.
Honolulu
Well-Known Member
The "Old Pro" taught me that the clutch release bearing can be taken apart using two opposed screwdrivers, and the grease cleaned. If the balls and race are not dimpled or scored, regrease, reassemble and on you go.
On the other hand, you have to remove the trans to get at it, no small endeavor for the one-guy-in-a-garage private owner, so you want to measure your chance of success against having to do it again. Look on the bright side, though: once you've done it, you'll have all the tools and setup to do it in one-quarter the time, next time.
You're going to have to remove the trans to access the bearing (which should be cleaned and greased once you're in there anyway). At that point though it would be nice to have another new release bearing on hand, I wouldn't install unless the old one is demonstrably in poor condition.
On the other hand, you have to remove the trans to get at it, no small endeavor for the one-guy-in-a-garage private owner, so you want to measure your chance of success against having to do it again. Look on the bright side, though: once you've done it, you'll have all the tools and setup to do it in one-quarter the time, next time.
You're going to have to remove the trans to access the bearing (which should be cleaned and greased once you're in there anyway). At that point though it would be nice to have another new release bearing on hand, I wouldn't install unless the old one is demonstrably in poor condition.
This seems like a possible cause of the noise I've heard in mine. Or maybe not.
For what it's worth, here's the link to the sound I recorded.
E9 Clutch related noise - mulberryworks.mp3
I recorded this shortly after I got my car on the road. At the time I thought it could be a throw-out bearing noise, but that seems less likely now.
You can hear the noise stop and start as I cycle the clutch pedal. There's a big hole in the passenger's floor so a lot of engine sound bounces off the pavement into the car.
Ultimately, the source of my sound isn't critical as I'm on the path to change from the 4-speed ZF to a 5-speed Getrag. I posted here more as an example of what kind of noises might fit the OP's issue.
In reference to the "Getrag rattle" I've heard about, it seems that it's something to do with loose (worn?) shift forks and can be annoying at idle. A friend had an early 7 series with it and it's a different sort of noise than what I've got.
Thanks for this recording. Your sound is in fact a bit like mine. (I will also make a video and post when I drive next).
What I don't want to do is go down a rabbit hole of pulling the entire trans and replacing parts and finding the noise still there. (My noise/rattle when idling is actually not that bad but suffering from OCD it is on my list to ideally fix. Thankfully my gearbox works smoothly, is quiet when driving and shifts perfectly)
I have also reviewed all the previous forum threads on the 'E9 gearbox noise' topic. These threads reinforce that it is certainly not easy to isolate and identify the worn part culprit or source of rattles and strange noises. Some of the comments such as 'it's a ZF feature not a bug' on this older post were rather hilarious.