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How Strong Are Rb25det Manual Gearboxes..

brizzi
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brizzi Collaborator

brizzi

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Just how strong are these gearboxes? Obviosly not too strong!! Went all out got rid of the rb20det 5 speed and put a rb25det 5 speed in tailshaft mods,speedo drive etc etc.. Driven for three months no noises what so ever.... Then second gear into third the smorn hit boost then bang! No other gears except second and fourth... And rattle all the way back home to get the stagea to drive to work... Does any one know the damage, by all them symptoms? :) Cheers if anyone can help? Im sick of changing gearboxes this is number 5 on the list of skyline gearboxes i have murdered! Anyone help? cheeers :)

R31Nismoid Grand Master

R31Nismoid

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Posted

The gearboxes are tough as mate.

Do you know the condition and the life of the box before you purchased it?

Thats most likely where the damage has come from. Previous owner :rofl:

If you've killed 5 boxes, then i think it could well be your driving

r33goodz Rookie

r33goodz

Posted
Posted

as r31nismoid said, these gearboxes are about as tough as any going around. that said, any gearbox will eventually break from constant 6k launches...may want to revise your driving style. also, when buying a second hand box, and go and get it rebuilt properly or at least checked out. a box that has been broken then rebuilt is better than a second hand box as you won't know the condition its in. not sure how you lost 1st and 5th gears, but it sounds like you have stirpped 3rd gear. i'm also assuming you still have reverse? :rofl:

R31Nismoid Grand Master

R31Nismoid

Posted
Posted
I want side step rev limiter strength! :(

They will take that no problem here and there

The enemy of a gearbox is traction... ie drag strip + slicks/sticky as rubber... and big power.

Also putting that kind of strain cconstantly on a box isnt going to help it either. Here and there shouldnt be much of an issue

I doubt there is anything that will ever last constant abuse

You shouldnt need to be doing that anyway, even if you are drifting... which if you need to do so, you need more skills and a better setup car

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