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Hey all

So i recently bought a R34, originally it was a auto and the previous owner has done a manual conversion on it, drives around fine and what not. But it has come to my attention that the gearbox used is one out of a VL commodore ,well i think it is if someone can confirm the origin of the gearbox it would be appreciated (yes i checked previous threads from years ago but there was nothing confirming it). Also is it worth finding a proper R34 manual gearbox and swapping it out to future proof it ?

Gearbox Details

  • Has casted the following code - RP71C #2
  • 5 speed manual

only half decent photo of majority of the gearbox i have on hand at the moment

20206092_1874834712768533_2074194155_n.jpg.d8f62cd69508735a331b1de949ba62bb.jpg

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https://www.sau.com.au/forums/topic/473558-r34-gearbox-rp71c-2/
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  • 1 year later...

Hemal, I’m in the exact same boat mate. I’ve tried researching it and have found that it’s fitted in r31,r32, r33, a31, z31. Not sure how true this is though as it seems anyone who has been asked this question all have different answers. I know it not much help but hopefully someone can clarify this for us. 
 

On another note I’m assuming your trans crossmember doesn’t bolt up properly. Only two bolts where holding my up. I decided to cut and re-weld my. Here are some pictures of how it turned out if you where wondering. Hopefully this helps someone out there 

C88434AF-5369-47CC-B70B-962350E55906.jpeg

4A27DF7B-DDA1-4C59-9193-062B097C92FE.jpeg

157E55BD-6C93-4E34-8F38-059FA1681D9A.jpeg

7E013CB0-3C33-43BC-99B0-BF4051295945.jpeg

12435597-735A-4BF8-8DF7-E3EFD2CDA872.jpeg

It's easy to tell. The RB20DEt box is literally half the size of the RB25 and VLT gearbox. The 25DET and VLT box are almost the same thing, but I think the code on the VLT box was MX7.

And there's no need to go cutting and shutting the gearbox crossmember. There are 3 (actually 4) labelled A, B & C that all align differently and allow you to put pretty much any box in any chassis, for the most part, so long as you get the right one.

And last tip. Don't turn the boost up on the R34. It will wear the little box out quite quickly.

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