Opening up a manual gearbox is always a fairly scary job, especially when there is no information about spare parts or how to take it apart. A year ago I was searching the internet because, for a project, I needed to separate the bellhousing from the gearbox in a way that would let me put it back together later. Some pressed it apart with a big HEB beam and M20 threaded rod, others simply went at it with a hammer — they all got the box open, but the methods were rather brutal and nobody showed how to put it back together, neither in writing nor on video, so I was on my own. Feeling my way in the dark I learned quite a lot, and even managed to get some information out of the ZF factory, which I'm about to share with you here.
In this post I'll describe how to take it apart as painlessly as possible. To start, here is a list of tools you may need for the job:
- Torx 30, 45 & 50
- 1/2" ratchet
- Extension for 1/2" ratchet
- Torque wrench (20 Nm)
- Straight nose lock ring pliers
- 17 or 18 mm socket (my memory fails me here)
- Heat gun
- Angle grinder
- Infrared thermometer
- Shaft seal remover, for convenience
- Flat-head screwdriver
- Ideally, tools to build a puller — but if you have the patience, in theory the bellhousing can also be removed by heating the bearings and tapping on the shaft. (The bearing inner ring ideally wants about 110 °C before things start to move.)
I'm listing the spare parts in English, as that makes them easier to find and order:
- Sealing cap with original ZF spare number 0501 317 873* as shown on Diagram No.1 with number 01.130 (price aprox 8 euros)
- Shaft seal with original ZF spare number 0750 111 403* as shown on Diagram No.1 with number 01.030 (price aprox 10 euros)
- Ang. Cont. Bearing with original spare number 0735 340 180* as shown on Diagram No.1 with number 01.100 (price aprox 60 euros)
- Ball bearing with NTN code 6308X35CS26 (you can find this roller bearing from any decent bearing dealership for 25 euros aprox. On diagram marked as 01.070.)
- Some liquid gasket (Victor Reinz is one of the best out there with price tag aprox 10 euros)
- Oil BMW MTF-LT-2 1.6 liters.
NOTE!
Diagram No.1
Let's get started! Like any proper gearbox, this one should have oil in it, so begin by removing filler plug 01.230 together with the drain plug at the bottom. Drain the oil into a clean container — any metal shavings can give an early idea of the gearbox's condition. Remove bolt 01.050 with guide sleeve 01.040. Seals 01.030 & 01.130 will definitely be destroyed during disassembly, so you can simply punch holes in them with a screwdriver, or drill them. The holes can then be used as pulling points for a seal puller.
With the seals removed you can reach the retaining rings and the lower shaft bolt, which also has to come out before going further.
Before you start prying the housing off, a few more bolts etc. need to be removed:
06.060 and 06.480 come out easily (a spring with a detent pin comes out from under 480) — just screw them out and that's it. Caps 06.830 and 06.780 are a different story, and without cleaning you probably can't even see what's going on there, so start with that — brake cleaner does the job. After cleaning, small retaining rings sitting in the gearbox casing come into view — with enough luck the cap pops out by itself under spring pressure once they are removed. If you're not that lucky, help it along with two small screwdrivers until the cap starts to move. Cap removed, take out the springs as well.
Now the real fun begins! As mentioned earlier, this gearbox can be pressed apart either with brute force or by heating the right parts. In my case I built a jig that pushes on both the upper and the lower shaft at the same time, as shown in Diagram No.3. Pushing on only one of the two shafts makes the casing tilt, and we don't want that. When building the jig, keep in mind that both bearings sit with an interference fit, so the pressing forces get quite large.
The bolts press directly on the shaft ends, so put a washer in between to avoid mechanical damage!
If you have patience to spare and no rush, you can also try heating. Metal has the handy habit of expanding when heated, and you can use that here. The idea is to heat both bearings until the inner ring reaches at most 120 °C, so it expands enough to release the shaft. If you're fitting new bearings anyway you can go above that temperature, but not by much, as the heat can start to affect other parts of the gearbox — if the bearing's plastic cage or grease starts to melt out, back off the heat. It's also important to direct the heat straight at the bearing inner ring and not let it wander elsewhere. Cooling the shaft at the same time with freeze spray or a wet rag can help too. This is where a laser thermometer to monitor the inner ring temperature comes in handy. Once the right temperature is reached, set the gearbox down and hit the shaft end with a hammer through a wooden block while supporting the housing with your legs. With enough luck the gearbox comes apart this way too.
So, like mentioned previously there are two ways to split this casing. If you are planning to build a puller keep in mind that it have to be quite bulky to keep up with forces. Both input & aux shaft are fixed to shaft via tolerance fitting so in normal condition there is no way you can just pull it off from shaft. Same thing goes with clearance between housing and bearing. Because there is two shafts you have to use 2 pushing points on puller to equalize the forces as indicated on diagram No.3!
Once you've done everything you needed to do, the gearbox has to go back together. Brace yourself — in my opinion putting this gearbox together is even worse than taking it apart. For everything to work out, it all has to be assembled in a specific order.
As shown in Diagram No.5, start by fitting bearing 01.070 into the housing. The bearing should go into its seat with light tapping, after which it is locked in place with a special plate and bolts.
Next, take one of the inner ring halves of bearing 01.100, heat it to 120 °C, oil the shaft and slide the ring onto the shaft as shown in Picture No.5.
From the other side of the housing, tap bearing 01.100 into place — it should go into its seat as easily as 01.070. With the bearing in place, take out the other half of the inner ring — it goes in once the housing is back on.
Before fitting the housing, it's worth cleaning the drain plug and the area around it inside the gearbox. I'd also recommend cleaning out the inside of the gearbox itself.
Putting the housing back on is, in my opinion, one of the hardest moments of the whole process. The gear selector linkage has to be in the right position, with its end running into the shaft seat inside the housing — in my case I had to take the gearbox apart twice more because the selector shaft was fussy and always went where it shouldn't. Heating also helps when refitting the housing, but for that you'd need a bigger oven to bring the whole thing to 120 °C (110 °C is probably enough). If you have a bigger press at hand, that should in theory do the job too.
When refitting the housing, don't forget to clean the flange faces and apply engine silicone so the oil stays inside. As you fit the housing, make sure the shaft ends shown in Diagram No.6 sit in their seats. According to the diagram, the pin on the end of bracket 06.170 has to line up with the seat on fork 06.050. The same goes for the lever on shaft 06.300.
As shown in diagram No.5 install bearing 01.070 by tapping it in to the casing. Secure it on place using locking plate with bolts.
With the housing joined back to the casing, fit the missing half of the 01.100 bearing inner ring — you can use the bolt on the shaft end to press it into place. Everything else goes back together in the reverse order of disassembly. Before filling with oil, refit the drain plug — its tightening torque is 35 Nm. Oil in, filler plug on, and you're done!
Many thanks to everyone who took the time to read this! The pictures are from the ZF spare parts catalogue, which I can share if needed. Just send an email to kasutamucustoms@gmail.com and I'll try to reply as quickly as possible.
Great write up, thank you for sharing this. I was curious about how to open this up also. Do you have a picture of the inside view of the bell housing half of the case? It sounds like the ideal way to seperate the bell housing is to use a beam and a bolt and use that to press it off the input shaft nose. It sounds like the case halfs are sealed with liquid gasket, no rubber or paper material, would you mind providing the part or description of the Victor Reinz sealant?
What was the reason you had to open it up? replacement of synrchos, bearings, or other parts?
Hi! Thank you for your comment!
Sadly didn’t find any picture from the phone.
For pressing you can use beam but it have to tolerate quite much sideway force and you need to press from 2 points equally- under input shaft there is another shaft nose what is hidden below sealing cap.
If I remember correct than originally there was a gasket from factory but you will be golden with liquid gasket like Victor Reinz sealant or something similar.
The reason why I had to split casing was that gearbox was bolted on Volvo t6 engine and bellhousing had to be welded. You can see some of this progress in my Instagram page: https://www.instagram.com/kasutamu_customs/
Hello you are like my savoir! I’m recently working on rebuilding my GS6-53BZ, may I ask where can I get parts no. 06.160 & 06.120(I assume they are the same?) And if you know the name of the parts in English please tell me also, I live in a country where most of BMWs are automatic haha, sorry for my armature English, look forward for your reply! Thanks
Hi!
Those parts are called “stop bush” in English. Best bet to find one is to source out who is your local Zf dealership in you country- for instance in Estonia it is https://kgk.ee/ . They can ask straight from factory.
Pretty happy I stumbled on your website. Any idea what the 06.080 part number is and how it can be replaced ? It seems like it is pressed in from the exterior of the gearbox ? I have one that has cracked so the spring it contain has popped out and it’s a real head scratcher.
Hi!
Thank you for your comment
You are probably correct- this stop bush is probably pressed into casing of gearbox from outside. I’m not sure how tightly it sits there but you can try to drill out center and then slowly pry out with small screwdriver or something similar.
I will try to send spare parts catalogue via email- there you can check for spare part number and try your luck!
Today i have ordered bearings 01.070 and 01.100 and another parts (sealing cap, oil, sealing ring, …). My transmission makes some noise when clutch pedal is not pressed. when i press clutch pedal to the floor, the rattle sound sudenly stop – probably these bearings. In our state is problem to order these bearings, so i have asked directly NTN. they offer BA2-0023B
35 x 73 x 30 and 6308LLUC3/5K NTN 40 x 90 x 23. They Told me that somebody ordered these bearings exatly for this transmission and it works, so i have ordered these bearing (i know that these bearings aro not directly from ZF, but when it will work, it will be great). Of course, thanks for your legendary write up.
Hi!
Thank you for your comment!
NTN should work just fine.
Glad to hear I can help!
Let me know how it went when the job is done.
Hi, I have the 53DZ gearbox connected to a 71 Ford Mustang 429 making 650hp/750Nm via a Tilton 3 disc rigid clutch. I I noticed that “SNX” wrote that the gearbox makes noise and it disappears when pressing the clutch – the same in my case. The guys driving drifting have experienced the same with a rigid clutch like Tilton 3 disc NASCAR clutch. The noise disappears also when rising up the rpm. I was told by a ZF mechanic that most probably the resonance is coming from the engine itself. The gear shifts as such are clean. In my Mustang the rear axle is rigid and the propeller shaft has an inch gliding action to compensate the suspension movements. The connection to the gearbox is otherwise rigid.
Not knowing how BMW has solved this but it not necessarily is a bearing problem. It would be interesting to hear what “SNX” found out and did he get rid of the resonance in the gearbox.
Sorry for late reply!
Sadly I have no feedback from SNX but it seems to be the deal when u are running rigid setup- vibration and noise have to go somewhere.
Om 606 and bmw gearbox gs6
Same shit, sputtering at idle
Hi Martin,
Thanks so much for your write up with photos and schematics. Really good stuff as I was googling for a while without getting the answers to my question.
Yesterday I was changing the oil on my GS6-53DZ for the first time, and stupidly removed 06.060 instead of the filler cap. I wasn’t paying enough attention. I had to get creative tool-wise to get access to it as well as it’s so close to the trans tunnel in my E88 135i. I don’t have a low profile T50 but used a ratcheting spanner on the shaft of the T50 to crack it and then was able to remove it by hand. I was shocked when I pulled out the pin and realised it wasn’t a plug, but had a tapered shaft with a point on the end. I then felt around and found the correct filler plug and realised how dumb I’d been.
Anyway, I cannot reinsert 06.060 by hand and was hoping I hadn’t messed something up inside the box. Looking at your photos and diagrams I’m thinking I just need to reinstall 06.060 with a low profile tool and I should be ok right? I’m guess the pointed and tapered end of the bolt will correctly locate into the shift fork?
Do you know what torque it needs to be?
Hi!
Thank you for your comment!
Happens to the best!
I believe it’s not so huge problem- there is slight play on the gear lift fork but nothing criminal when one bearing pin is removed. Small wiggle should guide it back to it’s position.
Sadly can’t tell about specific toque specs for that one but if you will measure the thread you can find necessary information from google.
Transmission make some noise when clutch pedal is not pressed the proplem is the bearing 01.070 seal two side 2rs it gets dry then make noise should be 1rs or remove 1 seal inside thé Transmission side the oil Will lubriquateth bearing
You can try to repack the bearing with grease if there is enough room to remove bearing plastic shield
Hi There! Thank you so much for this post…there is not much info out there about the inner workings of this transmission and how to take apart and rebuild. I’m hoping someone can help point me in the right direction here…in draining the transmission fluid from my GS6-53BZ (hopefully it’s similar enough), I found a small snap ring attached to the magnetic drain plug and I’m trying to figure out what part it is before trying to fix myself or find a shop to help. The trans is out of the car but was working well with no noise or issues before removal and i can cycle the gear selector through all gears with no issues now. The OD of the snap ring is 11.89mm and the ID is 9.25mm, smaller than part 06.780. Maybe parts 06.224, 06.184, 06.194, or 06.234 in the diagram above? Thanks so much!!
Hi!
If I’m correct the only difference bedween 53DZ and 53BZ are gear ratios.
Drain plug should not contain any snap ring- part number 01.230 on first scematic.
Part 06.224 should be o-ring installed on quide pin 06.220.
Mabey you can send me a picture about this ring and I will let you knw what I think: kasutamucustoms@gmail.com
Thank you for the quick reply, Martin! I have emailed you a photo. And yes, no snap ring from the drain plug, the snap ring was stuck to the drain plug because I use aftermarket magnetic drain plugs – ironically for this exact reason. I just hoped I’d never find anything on it and thankful I have it or else the snap ring would have just drained right into my drain pan and likely never would have seen/noticed it.
Hello, I’m looking for part 01.250, the roller bearing. I haven’t been able to find it yet.
Could you please give me the reference number for this part? Because it has unusual measurements and must only be sold by ZF, but I can’t manage to contact them, and there are no dealers near me.
It would be a great help if you could provide me with the reference number.
Thanks in advance.
Hi!
Reference number for this one is 0735 298 189
I hope it helps!
I will send catalogue also to your mail!
Bst Rgrds
Ammer
I see lots of complains where people have noise at idle, which disappears when clutch pedal is pressed or when driving. I had the same issue and turned out to be the reverse idler bearing
Hello everyone,
Does anyone have the complete workshop manual for the official ZF? I hear a clanking noise when I release the clutch. It sounds different depending on the release conditions or only if I accelerate under certain conditions. It’s like a “stenk” as if pieces of metal were moving. The dual-mass flywheel was half-marked, and I hope that’s it. The two parts were rubbing because half the flywheel had a long-marked half-flywheel mark. But the gearbox has 430,000 km, and I’d like to open it to check the status. Gearbox GS6-53DZ on Bmw E60 530D.
Hi
There is no workshop manual for this box. This was confirmed by ZF factory in Germany who said that this box is so called maintenance free and due to this there is no workshop manual. But they where kind enough to send me spare parts catalogue- I ill send it to your mail.
Flywheel is probable cause to the clank I believe. You can also change oil of the box and see if there is any metal shavings etc. – if none I don’t believe that there is anything wrong with box itself…