what is the weak spot in the gearbox

[machine]

hi guys , ive been reading for a few weeks , im in canada and really really want a gtir , just doing as much research as possible (for finding parts here , like ball joins and wheel barings , that kinda thing )


i am concerned with the gearbox problems i hear about .

what is the most commom things that can go wrong with them over 300bhp

i have rebuilt transmissions before so im not concerned with rebuilding . but id like to get a spare tranny (theres lots over hear since the gtir didnt exist and many sentra guys asre swaping the gtir motors in the fwd sentra and not uding the awd gearboxes) just to build it up .

thanks a bunch

 

[abyss]

the casing is made of chocolate.

 

[geoff pine]

Im sure some one will be on later to give you a more tecnical explanation

 

[Rishi]

Gearboxes are fine! Its the fact that the parts in them have generally had 15years of use and then you go trying to up the power..

I managed to strip the teeth off 5th.. But you generally find that its something else that fails to cause this like Bearing Failure. Its just general wear that causes fatigue a lot of the time...


Rishi

 

[Keira]

Gearboxes are fine!

no they're not :lol:

all this how you look after it and drive it bollox is utter crap, most of it comes down to luck with how long it will last.

go take one apart and look at the size of some of the gears, especially 1st and 2nd, look at 3rd - 4th selector fork (the others are fine, cant see why the didn't make a better job of 3-4tbh) have a good look at the casing, its a complete pile of shit tbh. Theres not alot in that box thats any good

me and al got hold of a damaged evo the other week and took the box apart, now thats a well made gear box, the gear box casing is made up of 3 seperate parts so the shaft is held at an extra point with a bearing, similar to honda gear cuffs that replace 5th gear, the whole entire box is much better designed and made, its no wonder they take much more power than ours.

 

[MarkTurbo]

Theres not alot in that box thats any good

I think that sums it up quite nicely :lol:

Gears = shite
Casing = shite
Selector forks = shite

I even broke 2 boxes on my car running standard boost :doh: Including mine i must have rebuilt about 6 boxes now and everytime its either stripped teeth or a snapped selector fork. You do get the occasional good one, the box in mine at the moment has had god knows how many 6000rpm launches and generally gets a lot of abuse but i know it only be a matter of time before it ends up as a heap of broken bits :wacko:

Actually i have just thought of one good bit of the box :shock: The magnet in the bottom comes in handy for picking up the bolts that fall into the gaps between the paving on my drive :lol:

 

[ashleygtir]

can't you get better quality bearings? or someone to fabricate a selector fork that will last???

 

[Keira]

bearings = yes
uprated 3-4 fork =yes

but you'll still have a pile of crap of a gear box

 

[abyss]

much would it cost to make a gearbox casing thats is made of a decent metal. Never really got an answer to this one.

 

[steve963]

the real question is whats the cheapest alternative for around 350bhp

 

[Fire & skill]

i thought of cryo treating a box, just couldnt be arsed removing it

 

[steve963]

so you can bring it back to life in 100 years...

 

[MarkTurbo]

the real question is whats the cheapest alternative for around 350bhp

Use a standard box and learn how to build them yourself ;-)

You can pick up broken boxes for about £100 these days and have enough spares off them to allow for a few box breakages. If you could do all the work yourself replacing a couple of stripped gears wouldnt even cost you £50 in parts, based on that i could go through 40 standard boxes before i'd be nearing what a quaife would cost :lol:

No point chucking money at shite :der:

 

[Fire & skill]

so you can bring it back to life in 100 years...

:lol: yeah, so some other poor bastard would have to get it rebuilt.



being honest mate its more the fact that i have this stuff at my disposal, i can easy get a - 80 freezer or i could blag my way into getting a loan of a -150 8)


in fact anyone want anything cryo treated, much cheapness? :lol: :lol:

 

[shinny]

Would You Be Able To Use A Different Box Off Another Car? Skyliner?

 

[Fast Guy]

Would You Be Able To Use A Different Box Off Another Car? Skyliner?

Off a Skyline, not a chance!!

Possibly with alot of work, new bellhousing, another transverse box could be made to fit, but is it worth the effort:?

 

[Rishi]

no they're not :lol:

all this how you look after it and drive it bollox is utter crap, most of it comes down to luck with how long it will last.

go take one apart and look at the size of some of the gears, especially 1st and 2nd, look at 3rd - 4th selector fork (the others are fine, cant see why the didn't make a better job of 3-4tbh) have a good look at the casing, its a complete pile of shit tbh. Theres not alot in that box thats any good

me and al got hold of a damaged evo the other week and took the box apart, now thats a well made gear box, the gear box casing is made up of 3 seperate parts so the shaft is held at an extra point with a bearing, similar to honda gear cuffs that replace 5th gear, the whole entire box is much better designed and made, its no wonder they take much more power than ours.

Hmmm... Looks like i stand corrected!.. :lol:


Rishi

 

[Fire & skill]

Would You Be Able To Use A Different Box Off Another Car? Skyliner?

i keep thinking that the celica st185 box could be adapted to fit, would be interesting to see how close they would be

 

[nismoboy]

i keep thinking that the celica st185 box could be adapted to fit, would be interesting to see how close they would be

i also think u could. they can take 500 easy.