Gearbox Attention Any Advice Appreciated

[elir32]

So it appears that my 4th gear is on the way out - I believe it's out of sync. Just starting to crunch when going 5th to 4th and sometimes 3rd into 4th-under higher revvs normally.

Does anybody know someone/rebuild gearboxes and have an idea on prices etc or rexomendations on who is best to see?

Or alternatively am I better off sourcing another second second hand box?

I'm running r33 s1.5 box in my 34 so I'd like to keep the push type clutch as it's only 5000km since fitted.

Any advice appreciated. Thanks

[Carbon 34]

dump the oil and put in Redline MTL or 80-90 wt oil,(NOT SHOCKPROOF!!!) that solves most cases without tearing the box apart. 4gear failure ??? normally its 2nd from ham fisted shifting

other synthetic oil wont do the same job to help the tranny .... believe me.

shockproof is too slippery for synchros to mesh properly dont use it on a 5 spd skyline

did you change the spigot bearing ???? if not that can cause the same problems when it goes

[Simon-S14]

I've got a good contact who does gearbox repairs.hes based in ne burbs of adel. prices very reasonable. Pm me for contact details.

[elir32]

I will give an oil change as suggested and see what that does. Gearbox has only been in for 5000 km - came from a 33 I wrecked and I know the previous owner had no troubles.

I Didnt put the box in myself -Someone did it for me as I was to busy at the time- but from memory the spigot bearing was replaced- the oil in the box prior to instalation was very poor and dirty and I would think that the oil put in since then-5000km- really should be replaced anyway.

Thanks simon- if oil change does nothing I will pm you regarding contact

[Luke_ENR34]

Wheelworx also do it I'm pretty sure.

[Simon-S14]

No they don't. They used to and the guy who did it is the guy I was talking about a few posts up. He works from home now and is am absolute guru when it comes to boxes

[Carbon 34]

yeah if the oil doesnt solve it mate and the clutch is installed right ,

then a good box builder is rare find. MV automatics are well known for autoboxes ... but nfi who can do 5 spds worth a shite . it takes a lot of special tools to rebuild boxes in most cases

Redline has been the only oil that seems to fix up 5 spds with borderline issues, I've tried all of them over a lot of years . amsoil would be my next choice but its super hard to find and expensive as hell.

watch out too redline comes in US amounts quarts ,gallons not litres so get enough for your box. about 100 bucks or so is normal cost and lasts for a long long time. if It wasnt such a pain to catch and refill I would let you have mine to test it in your box before buying it. its only 6 months old , maybe 3k on it .... but being dumped in two weeks to fit a new NPC clutch/flywheel, nismo short shift and tranny seals and refilled with new MTL ??? bring a bucket to the shop ..lol

and simon ash is running my car up on the dyno and the nistune afterwards , should be interesting

[elir32]

Thanks for the advice. I'm about to pick up a bottle from autobahn $114!!! Il drop it and replace and see what difference it makes and let you know. Hoping this solves it as I really wasn't budgeting for a rebuild or new box. Haha if I was in the city I'd swing by with a bucket cos it's always good being a tightarse .. lol..,but bein in the hills makes it probably a bit much work!

Clutch should be Installed right-it was done by a workshop-

Will let you know how I go shortly.

[sky30]

Every nissan box that i have had crunching gears, put in the blue shockproof and problem 100% solved.

[Carbon 34]

Redline doesnt recommend shockproof in the stock 5 spd Skyline boxes , it can cause problems with the brass synchros , "Redline Australia techs words when I called them for sponsorship/group buy discounts"

drag 5spd or ham fisted shifts it might protect the gears but not for street use

I run it in rear axle Nismo LSD , the temp is way lower and lockup is much much better, way better then the Nismo gear oil it had before, just odd when you have Blue smurfs blood in 140W that pours out of the bottle like coke not like the normal gear oil of old days.

if you want to see some interesting things, put normal engine oil in a cup and deep freeze it, synthetic in another , leave for a day , then try to pour it out, normal oil will be frozen nearly solid the synthetic will pour near normal. even 0W normal oil will freeze and need a spoon to get out,

(never use 0w in australia unless your running in the snow fields all the time)

[elir32]

Thanks for the advice Troy. Have changed it and it runs a hell of a lot smoother. Seems to of cleaned up the crunching with the small spin I took it on. If it does reoccur I will give you a pm Simon for contact details. Many thanks. Eli

[DOOM]

Please keep this thread updated if the crunch comes back or not. cheers

[elir32]

No problems- will do. Took it for another long drive up the south eastern freeway this avo and it has been smooth and noticeably different in every gear. It was crunching more under higher revs previously so next time I'm out giving it a bit more il see how it goes but il be surprised if it does crunch at all. Thanks again.

[Carbon 34]

your welcome, you will also notice the tranny temp is lower now , and power loss to the drivetrain is less = more power at the wheels , ever bit less friction helps

the same holds true for the engine oils etc. you can feel the difference instantly after changing to it . (it is the only oil certified for use on F18 engines that spin extremely fast. faster then a turbo )