Osg 5 Speed Issue

[Mr. Keets]

I thought I was alone on this issue but now I'm told a few people have experienced the same problem.

I have a vibration I believe comes from the OSG 5 speed...3rd gear light to medium acceleration only. I didn't realise there was a vibration there as the centre bearing in the OEM shaft(s) was on it's way out. It was only when I put in the one piece CF tailshaft, which I had checked for balance - no problem there, that I noticed it. The assembly of the box was outsourced by my tuner to a guy that has experience with these assemblies. The box does not have the billet centre plate.

Has anyone else experienced this problem? If so, do you know what caused it and what the fix is?

[Piggaz]

I asked the Yavuz (unigroup) about it tonight when I dropped off my car. He said he has never heard of that problem... but will check it out. I know it doesnt help us at all but hey, he might know what it is. I dont like our chances though!

[9krpm]

What speed does it wobble at and what tyres are on the car?

I had something similar to this when I had the ppg. The tyres were worn.

I changed to a new set of tyres and the problem went a way.

I have an OS gearbox now and don't have this problem.

I doubt that it is the gearbox.

[Piggaz]

^^

Mine deffo aint the tyres. Ive had two different sets on the car and exactly the same thing.

Its not really speed related either. Mine happens under load in 3rd. I can replicate that speed in 2nd and 4th and it doesnt happen. It isnt the driveshaft either. It has only happened since the OS Gearset went in.

[Mr. Keets]

9K...same a Paul mate. Wont do it at the same revs or speed in 2nd or 4th. Tyres are in good nick.

[Piggaz]

I might copy and paste your first post in the pommie forum man. Maybe one of the tuners have come across this issue.

http://www.gtr.co.uk/forum/118627-osg-5-sp...tml#post1117930

There it is.

Edited June 3, 2009 by Piggaz

[Piggaz]

Check that thread mate. One bloke has replied with some interesting info.

[Beer Baron]

9K...same a Paul mate. Wont do it at the same revs or speed in 2nd or 4th. Tyres are in good nick.

it's the box that's farked. send it to me, I need a spare one. cheers.

[Piggaz]

it's the box that's farked. send it to me, I need a spare one. cheers.

Do i get it back after you fix it?

[elrodeo666]

Piggaz..

Can you shed some light on the info you got! Was your box new or 2nd hand and you did o/haul

I'm looking at new OS 5spd with uprated input or possibly going the Auto Gallery Yokohama box..HKS boys here reckon the AG Yokohana is slightky better and smoother box

Hows the new shaft going??

Edited June 4, 2009 by elrodeo666

[Piggaz]

Piggaz..

Can you shed some light on the info you got! Was your box new or 2nd hand and you did o/haul

I'm looking at new OS 5spd with uprated input or possibly going the Auto Gallery Yokohama box..HKS boys here reckon the AG Yokohana is slightky better and smoother box

Hows the new shaft going??

OK. The guy from England was going to call me tonight. Might get a call tomorrow. I said to MSN or FB me but he was set on calling.

My box. The box i broke was a 11,000 KM old R33 box (got put in when the stroker went in). The new parts that went in was a OS 1-3 gear set with the heavy duty input shaft, and i put a new stock 5th in as i didnt need nor want the shorter OS gear. I also bought the billet centre plate oh and a few new synchros. Sealed bearings. Couldnt have done much more so it was practically brand new.

This is the post on the pommie forum from him:

"was built a good 2 year ago only found out the other day its a box problem,

have been told its not to much of a problem just a bit annoying, mine only happens in 3rd at 80mph, if your accelerating through the gears you do notice it, it can be fixed but obbviously its a strip down job, let me know if you have any joy with it mate, regards Dave"

Now my problem doesnt happen in any other gear apart from 3rd. 3rd seems to be a little noisier then the rest also. You notice it most when you come on boost and there is a driveline vibration. I dont know how else to explain it. When i put the rear sub frame alloy locking collars on MOST of it went away. Now I can only assume i have just masked them problem... not fixed it. The box doesnt crunch gears, its very direct and smooth.. just this damn vibration! I just cant see when pumping over 400 rwkw through a box and its vibrating can be a good thing!

The shaft. I had it balanced up. Put it in last saturday. Ive only done 20 odd kms on it. I'll get back to you with that after i drive the car in anger

[Piggaz]

OK. Just got off the phone to the guy in England. He said the vibration isnt detremental...just annoying. Its caused by one of the shafts not being balanced up right inside (im not sure which one.. he couldnt tell me). He said if you are REALLY worried about it you can give RB motorsport in England a call and they can set you on the straight and narrow.

His issues were the same as mine. Vibration in 3rd at around 80 MPH which is about 120 km/h (give or take).

So in summary. It can be fixed. But it means the box has to be rebuilt! BOOOOOOOOOO!

[Mr. Keets]

Thanks for the input guys and cheers Paul for posting on the UK site. I've sent off an e-mail to the OSG distributor over there that is mentioned in the thread and we'll see what happens. I don't know that any vibration in a g/box can be a good thing...but I'll wait for the verdict from RB Motorpsports. Then I guess I'll rebuild it

[Piggaz]

Ahh nice one.

The bloke i spoke to on the phone has put 8000 Miles on his box and so far has run a 10.7 @ 135 MPH. So he is putting a little bit more grunt out then what I am. I suppose thats some peace of mind.

[NYTSKY]

Hey Paul, where did you source the 1-3 OS gears etc from?

Mine needs rebuilding in a big way, PM prices if you can too.

[Beer Baron]

Piggaz..

Can you shed some light on the info you got! Was your box new or 2nd hand and you did o/haul

I'm looking at new OS 5spd with uprated input or possibly going the Auto Gallery Yokohama box..HKS boys here reckon the AG Yokohana is slightky better and smoother box

Hows the new shaft going??

the AGY 690 box is very nice. they are two kind of different things though. you can have OSG gearset with the AGY synchros. the AGY SS690 is a stock gearset but with new dual cone synchros where as the OSG set does not replace any synchros, it's just gears that are different ratio and have a different tooth profile (still helical though) on the gears. AGY can build you one using OSG gearset and their own dual cone synchros that has the best of both. they also do rebuilt/modded transfer cases which are worth doing as they do get a bit tired after 10 years+ of use. plus they have the 690R versions which have different ratios too. I haven't tried their extreme one which has a first gear that would take you to about 130kph! but I'm sure they are good too. get pretty exxy though. their hardcore one is super close ratio. would be great for drag and probably good circuit box too as you could use first on slow corners.

[BK]

I've got a similar issue in 3rd with my os box on my R33 gtr. It vibrates only in 3rd but I don't notice it unless you keep your hand on the stick. I've also got a brand new os giken set in my 32 gtr and it doesn't do this at all - totally vibration free in all gears. My old man who's a gun mechanic assembled both os boxes. He is putting it down to the 3rd/4th selector fork being a bit worn on the 3rd side in my 33 os box, making it vibrate when it's trying to hold it in gear. If it were a shafts, it wouldn't vibrate in only one gear.

Thinking of going back to a stock box for the 33 anyway as I don't like the ratios of 1st,2nd,3rd on my GT-SS turbos gtr. I think they are way too tall. Seems a good match for my T51 on the 32 though.

[Mr. Keets]

Selector fork makes sense.

Richard mentions the rebuilt transfer case. I had mine done with extra clutches...worth the effort

[Piggaz]

Hey Paul, where did you source the 1-3 OS gears etc from?

Mine needs rebuilding in a big way, PM prices if you can too.

$2768 from Greenline in june last year. That was for the 1-5 + input. However i bought a new stock 5th as i didnt want the shorter 5th gear.

Worn selector forks? My box was only 11,000 KMS old when i destroyed 3rd gear. Cant be that.. can it?

[BK]

Who's car are we talking about now ? Mr. Keets seems to have a R32 GTR so he would've needed all the same parts I needed for my R32 GTR, which would include a new selector on 3rd/4th. Piggaz your sig says series 3 R33 so you would still probably have your original fork. Your right it shouldn't be stuffed if it was new after 11,000km as my R33 series 1 GTR forks are still OK after 80,000km.

Shouldn't be as the 3rd/4th selector should be changed when you go to the late model synchros. Your old selector won't work if you had early sychros. Think about it, how else will the gear stick vibrate if it's only vibrating on one gear ? Has to be selector fork or something wrong with the synchro on that gear. Can't be the bearings or gears or it would be constant. I too have stock 5th in both boxes and OS input shafts.

The newly put together box is holding a monster amount of power on the R32 and it doesn't vibrate at all with the different fork.

I hate quoting dyno figures as the difference between mainline and dyno dynamics is so far out it's not funny but the R32 is holding onto a GENUINE 502 kw at wheels on a mainline and that ended up being 620 kw on a dynamics. Tuned 7 days ago by Willall.

Edited June 9, 2009 by BK