6 Speed (PTW) Gearbox Woes

N

niall

New Member
Wales
I am hoping somebody may be able to shed some light on some doubts that I have regarding my recent PTW conversion on my TDi90.

I started out with the plan to replace the DMF and clutch. The car originally had a GRJ gearbox, which I was planning to keep but soon discovered that it had huge diff bearing end-float, so I acquired a PTW 02A gearbox from a breaker rather than trying to chase another GRJ.

I removed the spacer/shim for the old GRJ gearbox between the engine and gearbox and replaced the clutch and flywheel with a new Luk DMF - no problems there.

I then cleaned up the PTW box and removed the old Golf-specific brackets and slave cylinder, etc. I added a new plastic headed pivot stud and a new release bearing 'sleeve'.

Here's where the problems started... When it came to the release bearing and fork, I had a bit of dilemma: The old GRJ release bearing fork was identical to the one that came with the PTW box, but the release bearing is different and the PTW bearing is about 3mm higher than the GRJ one (see images) which I replaced with a brand new LUK release bearing. I reasoned that the DMF and clutch were from the GRJ, so the new gearbox should also use that release bearing set-up...

I put the box back in, but noticed that the fork has quite a bit of free-play before the bearing contacts the clutch-you can push the fork in quite a bit before you feel it touch the clutch... This got me thinking, and I fitted the slave cylinder to see how the clutch might 'feel' as it seemed that there was quite a lot of free play. The clutch is *very light indeed* and does not feel like my other (standard) tdi90. The engagement also does not feel as 'positive'. It may be that the clutch is just new and therefore a bit lighter. However, I really do not want to put everything back together and discover that it all needs to come apart again for the sake of a release bearing - I'd much prefer to do that now that the gearbox is only temporarily in-situ.

So, my questions are: what have others with TDI90's who have converted to 6 speeders used for the release bearing - the GRJ set-up or the MYP/PTU/PTW one?

Am I being paranoid about the lightness of the clutch, or is there significant play in the fork before it contacts the clutch?

Any help /advice greatly appreciated!
 

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I am not sure Niall as it wasn’t me personally that did the conversion, however given your situation I would use the PTW one.

The good news is that this question would not be specific just to the PTW - anyone who has replaced their 5 speed with a NTG, PTU or MYP would have trodden this path also and should be able to advise.

One point to note - Audrey’s clutch is not overly light.
 
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Hi Niall. I have a ptw 6speed in the tdi (installed by wom) and the clutch feels significantly lighter than the clutch in the fsi.
 
Justin M said:
Hi Niall. I have a ptw 6speed in the tdi (installed by wom) and the clutch feels significantly lighter than the clutch in the fsi.
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I agree with the above, I questioned how light the clutch was in this car when collecting the above car from WOM after the work was completed as I had been driving in their 5 speed TDI while the job was completed. I think there must be different geometry to how the clutch hydraulics are mounted/its bore and stroke giving rise to the much lighter actuation. Was assured that this pedal feel was normal for converted cars.

I am driving an A3 8V with a 1.6 TDI now (the same as the donor for the PTW that went into Project Commuter) and this feels very similar to how the A2 felt after conversion.

Side note a QVX gearbox from the ultra models of A3 8V I would say is not suitable due to the very tall final drive ratio. Hmm maybe looking at the parts listing the PTW is very similar to the QVX gearbox, there doesn't seem to be any differences in their parts listings.
 
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How wide is the spacer you took out? That spacer is to push gearbox out to give room for the larger clutch diameter of the 90? Clutch is 20mm diameter larger over 75tdi?
Won't the free play rattle on idle with clutch out though?

If the bearing is too deep high, as in the photo, when you offer the gearbox to the engine you'll feel it touch the clutch fingers and it surely wont mate perfectly without pressing in a bit.

Never done it just a guess based on the design of a clutch :)

Hope someone replies soon for you Neil
 
CrispyEdd said:
How wide is the spacer you took out? That spacer is to push gearbox out to give room for the larger clutch diameter of the 90? Clutch is 20mm diameter larger over 75tdi?
Won't the free play rattle on idle with clutch out though?

If the bearing is too deep high, as in the photo, when you offer the gearbox to the engine you'll feel it touch the clutch fingers and it surely wont mate perfectly without pressing in a bit.

Never done it just a guess based on the design of a clutch :)

Hope someone replies soon for you Neil
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The spacer has nothing to do with it. If I left that in, the problem would actually be exacerbated not reduced! The reason for that spacer on the GRJ gearbox is not diameter, it is that the casting of that gearbox bellhousing is not 'deep' enough to accommodate a DMF...

The MYP/PTW/PTU family of gearboxes, *only have DMFs fitted* , so there is no reason to include it.

>>If the bearing is too deep high, as in the photo, when you offer the gearbox to the engine you'll feel it touch the clutch fingers and it surely wont mate perfectly without pressing in a bit.

I don't know that it is -'too deep' or not sufficiently 'deep' - that is kind of why I posted this question: to see what release bearing others have used 🤷

>>Won't the free play rattle on idle with clutch out though?
No, why would it? The slave cylinder takes up that free play...It just seems like I have a lot of it at the moment...
 
I have a PTW (installed locally) on my BHC, and recently an NTG fitted by WOM to my AMF. In the latter case they did it properly, the casing was milled down the 4mm to remove the extra metal not needed with the single mass flywheel - the PTW was fitted without machining. In both cases the only difference I can tell is in the slightly shorter and more positive throw of the gear lever - smoother on the NTG as they also set the cables properly whereas I just did enough to make it work with the PTW - there was no difference in the clutch pedal weight or feel before or after as far as I can tell. New clutch fitted in both cases - don't know about the release bearing in the PTW. Occasional slightly rattly noise at idle on the PTW that goes away when you depress the clutch but otherwise they both drive very nicely without issue. Appreciate it isn't a 90, so my comments are only really about the PTW/NTG conversions and clutch pedal feel in general.
 
Ok i understand the spacer bit, it moves the bell housing back to allow for the dmf thickness.

What I meant was if the release bearing is too think surely it will press the fingers when offered up to the engine, if it doesn't then surely that will give you less freeplay than the thinner grj bearing?

I wonder why audi built a gearbox that didn't fit ?! Odd one, not sure grj used anywhere else?
 
Robin_Cox said:
I have a PTW (installed locally) on my BHC, and recently an NTG fitted by WOM to my AMF. In the latter case they did it properly, the casing was milled down the 4mm to remove the extra metal not needed with the single mass flywheel - the PTW was fitted without machining. In both cases the only difference I can tell is in the slightly shorter and more positive throw of the gear lever - smoother on the NTG as they also set the cables properly whereas I just did enough to make it work with the PTW - there was no difference in the clutch pedal weight or feel before or after as far as I can tell. New clutch fitted in both cases - don't know about the release bearing in the PTW. Occasional slightly rattly noise at idle on the PTW that goes away when you depress the clutch but otherwise they both drive very nicely without issue. Appreciate it isn't a 90, so my comments are only really about the PTW/NTG conversions and clutch pedal feel in general.
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Thanks for your input!
 
CrispyEdd said:
Ok i understand the spacer bit, it moves the bell housing back to allow for the dmf thickness.

What I meant was if the release bearing is too think surely it will press the fingers when offered up to the engine, if it doesn't then surely that will give you less freeplay than the thinner grj bearing?

I wonder why audi built a gearbox that didn't fit ?! Odd one, not sure grj used anywhere else?
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At the risk of repeating myself again: I don't know if which release bearing is correct - that is why I am asking! I don't even know if it is the problem.

Audi don't "build" anything, the VAG group design stuff for maximum reusability across their brands. The gearboxes are all generic, they need to fit different vehicles - its a concept known as economy of scale. The group responsible for the A2 decided to fit a DMF to the 90PS engine and rather than casting a new bellhousing and all of the cost involved with that, they put a shim/spacer in between the gearbox and the engine. The gearbox fits just fine.
 
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When I fitted the MYP into my AMF, the clutch was much lighter than it was before, I put it down to a new and better clutch. As above, the 2 release bearings were different, the new bearing was deep than the original
 
niall said:
Many thanks indeed!

Do you know which release bearing was fitted?
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Don’t remember the make, it was a cheap eBay clutch as it was originally a scrap car so didn’t think it was worth blowing cash on, but it was deeper as I wondered if the old one had somehow worn down, which of course it hadn’t 😂
 
datsundrew said:
Don’t remember the make, it was a cheap eBay clutch as it was originally a scrap car so didn’t think it was worth blowing cash on, but it was deeper as I wondered if the old one had somehow worn down, which of course it hadn’t 😂
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Brilliant - I think that gets me closer to the answer and what I suspected - many thanks!
 
niall said:
At the risk of repeating myself again: I don't know if which release bearing is correct - that is why I am asking! I don't even know if it is the problem.

Audi don't "build" anything, the VAG group design stuff for maximum reusability across their brands. The gearboxes are all generic, they need to fit different vehicles - its a concept known as economy of scale. The group responsible for the A2 decided to fit a DMF to the 90PS engine and rather than casting a new bellhousing and all of the cost involved with that, they put a shim/spacer in between the gearbox and the engine. The gearbox fits just fine.
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Now now just tying to help. I was giving ideas for you to ponder or physically try like offering up the gearbox with the larger bearing. Sorry you misunderstood my message. Hope you get your answer soon Sir.
 
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