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4th gear sychro worn

Sleepergm
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Sleepergm Collaborator

Sleepergm

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Hi all,

 

suspect this is a common problem. I think I missed 4th gear a bit when I shifted down from 5th. Now it grinds into 4th with the downshift. Is it the sychro and what do I need to replace when I open the gear box up? 
 

added a photo of my new titanium intake I just installed and built. 👍💪

8dda622d-da7f-4c96-9082-e616d77527fa.jpeg

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GTSBoy Grand Master

GTSBoy

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More likely you've taken the teeth off the gear. Not the helical main gear teeth - the little pointed teeth that are what actually engages the gear. These work with the synchro rings, but they are not the synchro rings. The synchros are the brakes that allow those teeth to mesh.

Anyway, it's very unlikley that you've worn the synchro, much more likely that the points are knocked off the teeth.

joshuaho96 Veteran

joshuaho96

Posted
Posted
19 hours ago, Sleepergm said:

Hi all,

 

suspect this is a common problem. I think I missed 4th gear a bit when I shifted down from 5th. Now it grinds into 4th with the downshift. Is it the sychro and what do I need to replace when I open the gear box up? 
 

added a photo of my new titanium intake I just installed and built. 👍💪

8dda622d-da7f-4c96-9082-e616d77527fa.jpeg

IMO just buy a whole R33 transmission and swap the whole thing. Use a palm nailer/air hammer with a roll pin punch to drive the shifter rod end roll pins out. The rod end is discontinued so don't break it. Use gasket dressing on the OEM paper gasket instead of RTV. I personally would not pry on the shifter cover tabs, I broke one trying that instead of just smacking the side with a dead blow rubber mallet to shock it loose from the RTV the last mechanic applied. If you can't get the flanges totally clean and free of any residual RTV and/or you might have a gap that is bigger than it should due to flange damage use RTV on that surface instead of the OEM specced anaerobic sealer. Anaerobic sealer is most likely the right sealant for the job, it's just too easy to mess it up with too large a gap or bad surface prep/roughness seemingly.

If you do rebuild what you have it's for a whole gearset that can take high torque. Don't bother with OEM at that point.

Sleepergm Collaborator

Sleepergm

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29 minutes ago, joshuaho96 said:

IMO just buy a whole R33 transmission and swap the whole thing. Use a palm nailer/air hammer with a roll pin punch to drive the shifter rod end roll pins out. The rod end is discontinued so don't break it. Use gasket dressing on the OEM paper gasket instead of RTV. I personally would not pry on the shifter cover tabs, I broke one trying that instead of just smacking the side with a dead blow rubber mallet to shock it loose from the RTV the last mechanic applied. If you can't get the flanges totally clean and free of any residual RTV and/or you might have a gap that is bigger than it should due to flange damage use RTV on that surface instead of the OEM specced anaerobic sealer. Anaerobic sealer is most likely the right sealant for the job, it's just too easy to mess it up with too large a gap or bad surface prep/roughness seemingly.

If you do rebuild what you have it's for a whole gearset that can take high torque. Don't bother with OEM at that point.

I was actually just planning on replacing the fourth gear parts in the gear box that I broke … like the synchro hub or cone. And any other parts I need once I open up the transmission. That a bad idea? The rest of the gears feel tight. these parts shouldn’t be too much … just the labour here won’t be cheap. Just replacing these in HK would be around 2k aud including labour. 
 

how much is a new r33 or r32 transmission? 
 

thanks for the good info as usual 
 

 

 

joshuaho96 Veteran

joshuaho96

Posted
Posted
3 minutes ago, Sleepergm said:

I was actually just planning on replacing the fourth gear parts in the gear box that I broke … like the synchro hub or cone. And any other parts I need once I open up the transmission. That a bad idea? The rest of the gears feel tight. these parts shouldn’t be too much … just the labour here won’t be cheap. Just replacing these in HK would be around 2k aud including labour. 
 

how much is a new r33 or r32 transmission? 
 

thanks for the good info as usual 
 

 

 

32010-RHR30 is the Nismo Heritage transmission. I paid 1500 USD or so for mine.

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joshuaho96 Veteran

joshuaho96

Posted
Posted
3 minutes ago, Sleepergm said:

I see on rhdjapan they are under 1500 usd but is that a complete replacement for my transmission? Or just the case? 
 

the r34 getrag transmission swap is like 15k usd lol. 

It is the entire transmission BUT you must swap in your old transfer case. There is no transfer case on the back of it. Comes with throwout bearing for the OEM pull clutch and Super Coppermix Twin pull clutch, new clutch fork, pivot, cotter pin, washer, and clutch fork boot as well.

Keep in mind shipping is killer for such a giant piece of metal. I got mine from Trust Kikaku USA which shipped a container full of them to Long Beach and I had to pick it up from their warehouse.

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Sleepergm Collaborator

Sleepergm

Posted
  • Author
Posted
4 minutes ago, joshuaho96 said:

It is the entire transmission BUT you must swap in your old transfer case. There is no transfer case on the back of it. Comes with throwout bearing for the OEM pull clutch and Super Coppermix Twin pull clutch, new clutch fork, pivot, cotter pin, washer, and clutch fork boot as well.

Keep in mind shipping is killer for such a giant piece of metal. I got mine from Trust Kikaku USA which shipped a container full of them to Long Beach and I had to pick it up from their warehouse.

What’s the labour like on it? And how much better is it than the stock one? Guessing a lot stronger. 
 

I would be shipping from Japan to Hong Kong so not that bad… 

GTSBoy Grand Master

GTSBoy

Posted
Posted
11 hours ago, Sleepergm said:

What’s the labour like on it?

About a quarter of what you want to do. It's only R7R, not R&dismantle&replaceparts&reassemble&R.

11 hours ago, Sleepergm said:

And how much better is it than the stock one?

? It is stock.

12 hours ago, Sleepergm said:

ear parts in the gear box that I broke … like the synchro hub or cone

I already told you, you will NOT have broken those. It's f**king 4th gear for Christ's sake. You just chipped the teeth off.

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