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It was attached to the gearbox sump plug! :Bang:

haha ..... argh ..... faaaaaark ....

Put Motul gear 300 oil in there .... helped a little bit but still crunches badly going into 4th.

Any other solutions? Or will I have to get a new box?

Could it be to do with my clutch pedal travel or something, as I just put a new clutch in about a month and a half ago and I'm sure it was worse when I got the car back.

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No oil is going to fix this problem. Unfortunately you have to bite the bullet and buy another 2nd hand box from a wrecker, or get yours rebuilt. It wont be long before the metal circulates and starts busting the other gears too.

What clutches are u blokes using?

I've been running a Xtreem 30% Organic full faced clutch, it has got quite a bit of give in it as a flat change in to fourth will feel a little spungy. Third will chirp though.

I'm about to go the heaviest Xtreem clutch that is a 1058kg pressure plate with a cushioned ceramic clutch that has 12 puks. I know of this clutch holding ~300rwkw with no slippage, (Matt's R33).

I am sure as soon as I go the heavier clutch the box will die.

I've got a 9 puck organic with a 2500lb pressure plate in mine ... before that I think it was a brass button one that came with the car.

I launch the car hard but I wouldnt have thought that it would affect 3rd and 4th (3rd crunches a bit too now).

What sort of money are we looking at to rebuild 3rd and 4th synchros do you know?

Or to get the whole box rebuilt?

I re-counted.. Mine also has 9 puks on either side, the puks look a dull orange with specs of dark grey through out it. Previous organic clutch's I have seen tend to be more light grey, a bit brake pad looking.

A 2500lb is also the same pressure plate as mine.

Do you find it hard on the ol' left leg at a set of traffic lights.

I had a HD clutch put in a VS 5ltr Commodore I used to own, that used to make my leg shake at a set of traffic lights or when waiting to pull out in traffic.

I used to rebuild my 4 Speed single rail box in my TE Cortina, I constantly used to do syncro's & front main bearings.

To replace just the syncro's is just as much work to also slap in a set of new rear and main bearings.

Generally the rattle from a gearbox that you get & can hear when riding the clutch to move forward a little in say Mc Donalds drive through is the layshaft bearings, the lay shaft in the 4 speed g/box was a solid shaft with different sized gears attached, they all moved at once. A solid metal shaft would slide through the middle of this layshaft with hundreds of tiny roller bearings. It takes a long time to replace those as you need to stick them on to the solid metal shaft with grease then carefully slide it in the middle of the layshaft hoping you don't hit the sides to much as to dislodge the roller bearings. The layshaft bearings don't have to be replaced and generally arn't. I had the VS 5 speed g/box rebuild and specifically asked for the layshaft bearings to be replaced. Got the g/box back and they screwed me. The rattle was still there.

I knew from experience with the 4speed that the same rattle noise was definately the layshaft, if I didn't replace the layshaft bearings the rattle would stay.

From memory the parts for the 4 Speed Single Rail box (syncro's, front/rear main bearings, layshaft bearings cost me around $100)

To get some one to fully rebuild the gearbox I was looking at around $800-$900. I could have got jobs done for $450-$500 however I highly doubt they would have replaced the layshaft bearings.

Jimih,

Thought about an RB25 box? Bit stronger than the Rb20 one. Rebuilding is going to cost you a fair bit, gearboxes are labour intensive. Theres no point in doing it by halves either, because as soon as you fix 2 synchro's something else will break and youve gotta pay labour on taking it out again.

Jimih,

Thought about an RB25 box? Bit stronger than the Rb20 one. Rebuilding is going to cost you a fair bit, gearboxes are labour intensive. Theres no point in doing it by halves either, because as soon as you fix 2 synchro's something else will break and youve gotta pay labour on taking it out again.

Yeah 33 box would be good ... but my car is 4wd so I need a GTR box of some description I think :(

Joel: yeah I think the box has copped a bit of a punishing. The tyres are 255's all round, 4wd and heavy duty clutch. So I think the gearbox takes a fair amount of pain. The pedal isnt too bad on the left leg though :(

The motor's coming out soon anyway so I think I'll just change the box to a GTR box when the new motor goes in ...

Cheers anyway fellas! :D

hey jimih you dont have to buy a new box, my gears were crunching in 3rd and 4th, soi had the gears modified, costs about 50 bucks per gear, and 200 bucks labour, now it doesnt crunch and goes into gear much easier,..

hey jimih you dont have to buy a new box, my gears were crunching in 3rd and 4th, soi had the gears modified, costs about 50 bucks  per gear, and 200 bucks labour, now it doesnt crunch and goes into gear much easier,..

Wreckedhead, where did you get the gears from, were they new gears or only modified the existing cogs?

hey Craved sorry i made a mistake i didnt get new gears he bought new syncros for me and had the modified every 2nd or 3rd tooth was taken off.i had my box stripped to see all the gears and if there was any damage, he told me for a 9 year old box, it looked almost brand new inside, no damage to any gears, the only problem was when i was in fifth it was very hard to gear down to forth, but the new syncros fixed that up stright away, now going through the gears is much easier...

but i can give you the number of a place which can help you modify your box or basically do what you want to it

Joel,

Try telling that to my bucket of bolts gearbox. Pretty much stock standard car just over 100,000k's and it sounds horrendous, like its on its last legs. From experience and listening to many many issues RB20 owners have had with them, its my belief the box isnt so tough.

Red17

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