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hey guys

i just blew anotha gear box in my r32 gtst

2nd one in 3 months..

i have 215rwkw and a exedy brass button clutch with carbonic inserts higher clamp rate etc which probably isnt doing wonders for the 20 box..

so is it time to go the 25 box any other ways i can get around braking them so fast both boxs 2nd n 3rd gear almost no teeth left..

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i didnt think i treated it to bad but i guess the 20 boxs r just crap! pretty sure they r just a vl box with double syncros?

They are similar to the MF5 (I'm pretty sure is the code for it) in the VL's but there are slight differences. double synchros in 1st and 2nd and something else i think.

I had a mate shear the input shaft in his 20 box doing a launch at the drags with a button clutch, only had 190rwkw as well so a harsh clutch is probably not great for the box haha

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i didnt think i treated it to bad but i guess the 20 boxs r just crap! pretty sure they r just a vl box with double syncros?

In my experience, Nissan gearboxes are pretty well bullet proof. You really have to be brutal to it to break it.

I'm pushing 180 AwkW through my R32 GTS4 gearbox (RB25DET driving through an Exedy HD clutch), and it has never even looked like failing.

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Luck of the draw and driving style...but they are weak, and they are 20 years old now...go get an RB25 box. There's a reason Nissan put a bigger box in their car with 187kw, instead of just using the RB20 box.

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I've broken two of them but that was just input shaft bearing failure due to too many 2nd gear clutch drops, nothing as catastrophic as what you have done!

Going to the RB25 box was awesome though, takes all the abuse I deal and just shrugs it off.

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I had an R31 drifter with a RB20 turbo with the same clutch as yours, When the stock gearbox blew, i upgraded to one out of a R33 and the ratios and overall feel were so much better. Definately spend the bit extra and upgrade if you're giving it, the only problem i had was the speedo is different and i needed to use a speedo drive out of a navara or something.

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the only problem i had was the speedo is different and i needed to use a speedo drive out of a navara or something.

That's not a problem, just a part of the conversion process - plenty of info on here from myself and others that have done it.

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well i actually thought it was because you had a button clutch. those things really bite and can shock your gearbox something rude.

It is definitely a factor, clutch is supposed to be the weak point in the drivetrain. Upgrade clutch = shift stress onto gearbox and diff.

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yeh i new the clutch was a big factor in it.. well i went and got a 25box last nite with the slave cylinder and whole drive shaft.. so we r going to start the conversion tomoro nite.. see how it goes

Make sure you've got a welder and some flat bar handy.

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