Before I get blasted yes I have searched this and I know a similar question was asked in January, however I need a little more info. My Zed has the afforementioned 2nd and 4th gear grind however the majority of the noise is after the gear has been engaged. Should MT-90 still fix the problem or will this only solve crunching during shifts (not really a problem) Do I need new synchros or can I make do with $100 worth of oil. Thanks for your input.
A fwe things could happen Firstly, the new oil will most probably make a difference to the sound and feel (always seems to), however, it may not prevent ur syncros wearing further (may delay, though). Try the oil, and if it doesnt work out, then its 100bux wasted. BUt if it does work, then its a gearbox pulldown worth of moeny saved. Just as a sidenote, certain gearboxes from Toyota respond very positively to better lubrication, u might find the same.
I believe MT90 is for synchros, Lightweight Shockproof is for protection of the gears. Both have a an effect on improving the other aspect. i.e. MT90 does provide some benefit to the gears and Lightweoght Shockproof does provide some benefit to the synchros. If your problem is more gear related, I'd go the Lightweight Shockproof, if more synchros, the MT90. I have Lightweight Shockproof and this has also almost completely removed any crunching. It now only happens very occasionally when changing into 4th (if I make a sloppy change). Sorry to add to your choices. btw, see the tip in the Tech Section on an easy way to fill the gearbox. cheers, Peter
just out of interest, does anyone know how much it is to replace the synchros, like how much for the parts and the labour? cheers
Rebuild I had a really bad grind going from 3rd to 4th and switched to lightweight shockproof. NO difference. Called redline and they said MT90 so I went to my local redline dealer and he said you're wasting your money if it's broken it's broken oil isn't going to change that. Called UAS same response if lightweight shockproof hasn't made any difference (which it didn't, not the smallest bit) your box is shot. So tried for a while to get a box from the wreckers best (in fact only TT 5-Speed) I could find was $1200 + interstate shipping for a box with about 50,000kms. Ended up calling getting it rebuilt (new synchros, baulk rings, bearings etc) for $1700 at a joint in Sydney called Gearbox Express (contact details in my sig). So yeah in my experience sometimes broken is broken and you just need to repair it!
Fingers crossed Here's hoping that the oil will do the job, I guess its kind of an outta sight outta mind solution (well out of hearing anyway ) but i definitely don't have $1700 for a complete rebuild atm. Thanks for the help... i'll let you know if it works or not.
I've tried MT-90, heavyweight shockproof and now I'm about to try lightweight shockproof. MT-90 did nothing to improve my gear changes but has worked for many others on this forum. Heavyweight shockproof worked well but the oil in my gearbox was recently replaced with some other brand of oil when I had my clutch replaced. So now I'm going to try lightweight shockproof.
