Hi guys, Im not hoping to make any serious decisions fast but I just want an opinion on what I should do. My 89 gearbox is getting a bit sloppy, mainly the syncros aren't fairing so well, so gear changing isn't enjoyable like you'd want. Firstly if it could e anything other than the syncros, please advise me! Im not too great. So my options I have at the moment are : -Put up with it for now hoping it doesnt die, and Wait for engine pull in a year or two then replace/rebuild the lot. -Pull the tranny by itself now, and rebuild/replace(keep in mind Im a few years off finishing my degree, ill wait until I have the money) -Keep trying other things to try and mask the problem -anything in between I have never rebuilt a tranny, so I'm also asking the difficulty of it, in practice, theory seems easy enough. Thanks in advance! Kyle
Have you tried the redline or nulon solution offered in your original thread about syncro issues ? http://www.aus300zx.com/forum/showthread.php?t=327581
What did you try, both ? Is your clutch disengaging, ie is there free movement of the pedal before it engages, are you depressing the clutch fully ? Lose shift in gear > http://www.ttzd.com/tech/bushingstech.html Bush options > http://www.z1motorsports.com/advanc...n_keywords=1&plural=1&s=1&keywords=shift+bush
MT-90 Only, finding the nulon n70 is the third option of trying to mask the problem. Is there anything else you can think of that could cause my issue?
Yeah its worn out. Above I asked if the clutch was disengaging properly and are you depressing it fully, the reason being is synchronisation of meshing gears will work ideally on gears that are not being driven buy the engine. If you have tried the redline and drive to the gearbox is being disengaged via the clutch and you still have issues its most likely a box rebuild or replace situation. As far as rebuilding it yourself, on the basis that you are asking I would say not likely, as some specialist tools are required see page MT-2 and MT-3 in the factory manual., and these will probably cost you a pretty penny, as in the labor cost of a specialist to do it. (yes I know it can be done with a corkscrew a chopstick and the handle of a 1932 kettle.) A gearbox rebuild looks "straight forward" like an engine rebuild , given that you are asking the question and rely on the car for transport I would say doing the job yourself is highly unlikely. Most mechanics would get a specialist gearbox rebuilder to do the job. You would be more likely to try and replace the entire box with a good second hand unit. If your keen and have jacks, stands and good basic tools it would be a reasonable thing to attempt.
he wants to eventually do an engine and gearbox build on this car. Wouldn't he be better off getting one of those $1800 '98 gearboxes shipped to his door and put that in (leaving the engine until after he finishes his degree in a year or two). If the engine doesn't last another two years, well he still has a good gearbox (with papers) to sell.
Yeah but I don't think he has the money to go that way at this stage. $1800+$400 ship = $2200USD = $2400AUD +++ to do it right clutch flywheel fluids etc etc, easy $3000+ If its that bad I don't think much could be lost trying the Nulon G70 product if you have already tried Redline. http://www.supercheapauto.com.au/on...fferential-Treatment-125g.aspx?pid=1397#Cross It will get worse, whether you can put up with it for 1-2 years, well only you can answer that.
Hey Mate Post a video on you tube so we can see how bad it is Its really hard to give advice on something we cannot see or hear. Based on what you have said so far - I am inclined to say don't worry about it until you have got some money and keep driving it and hope it doesn't die a crushing death. But I am really reluctant to say that because I don't really know how bad it is - If its crunching like your corn flakes, squealing like your girlfriend and so sloppy it reminds you of a grandma hooker it may not only be near the kiss of death, but it could cause you more trouble than just a gearbox in the end when it explodes like a need another seven again space shuttle. Post a video mate so we can truly help you with a better informed decision. Sincere Regards Jamie
The gearbox is 25 years old, it stands to reason there will be wear in it. As brisz has mentioned, continue to drive it & it will only get worse. A used gearbox would probably be your best option, just make sure you can test drive it prior to purchase. Alternatively, you could put the money towards replacement parts & overhaul the box yourself, however you will need a few extra tools apart from a hammer & shifter to do it. You won't know how much you're going to be up for until you get the box apart. Perhaps a forum member has overhauled their gearbox & may be able to offer an approximate cost on parts?
What makes me suspicious is he refers to syncros, as in all of them and doesn't refer to a specific gear (although he did in his first thread.), which is why I tried to discuss clutch with him, but no response to questions regarding this. Could save alot of time and money.
When he finishes his degree he might look at his student life car and change his mind about the rebuild project. The money on a new gearbox won't be wasted in his grand scheme (whether he sticks to plan or is too well off in new profession to care) If he can get the new gearbox, sync with a tech day then he will have minimal downtime. And there will be a used gearbox that others can help him check out and rebuild and sell. Yes, he just needs that cash injection upfront.
have the shifter busings at the base of the shifter been replaced? if not, this can make a massive difference to shift feel and play in shifter itself.
Clarifying, the engine was rebuilt about 20,000 km's ago, so i dont have any suspision of the engine dying, the transmission is the only problem, not pointing to anything specific. I will get a video tomorrow of it if the nulon doesnt ease it off. @Jinxed, The bushing havent been replaced, I will look at these and get back about it. @Brisz + East Coast z + QLDZDR, Sorry for not being as specific as I should have been, 4th and 5th are the only crunchers above 2krpm, although downshifting throughout the gears is supplying a fair amount of resistance across the gearbox. Although in saying this before Gear oil change third was the same. I have just bought some Nulon g70 which I will find out in the morning its effect. Apart from that Im going to recheck slave cylinder(Im really hoping for another cause) So would syncing up with a tech day be my best bet for rebuild? Replacing is the other option, which I can do here..
second this - always good advice from east coast but would add - he says money is really tight - may not be able to do this - the second hand option could be the go - if money permits post the vid if you can - we will know a lot more seeing and hearing it I wasn't referring to the motor at all?
Nulon G70 had a reasonable effect, its not too bad, although into 5th is still slow, and has a high grind rate if pushed ( I dont push it im patient, dont shoot me) Video to come when I get home from Uni, although this is after g70, the problem was two fold as bad before. The video will show the resistance and the synchros catching up before I can change mainly entering 5th, 4th has improved a lot. Thankyou for that and sorry I didnt try it earlier, I will now be repping nulon g70
Adjust the clutch and give it a flush? Just to start with a low-cost option. EDIT: http://www.300zx-twinturbo.com/cgi-bin/manual.cgi The day I picked up my zed,1st gear went AWOL on me in peak hour traffic driving through melbourne. 2nd was crunching a bit and every gear was hard to click in. Adjustment and fluid flush made it sweet, except the 3->4 shift would crunch only at high rpm. A tech day may get your gearbox pulled/swapped, but it won't get it rebuilt!
