I have read some past posts on what oil(s) are best to use. My 2007 second syncro is starting to get tired (only 104,000 K's on it). I read that on the forum that a 50/50 mix of Redline MTL/MT-90 shows good results.

-Is MTL/MT-90 synthetic?
-Does anyone have an update if this really does work?
-Any other suggestions welcome as I'm rather puzzled as there are so many choices out there, including the OEM stuff.

Thanks, Pat

 

Redline MT-85 ( http://www.redlineoil.com/product.aspx?pid=140 ) is the most recommended gear oil for Z33/Z34. It is the only product on the market (except Nissan gear fluids) that have adequate friction modifiers to provide enough slip n' grip for our transmissions.

Problematic is the fact that your '07's 2nd gear synchros seem touchy (as the 3rd gear synchros on CD001 to CD008 seem more prone to 3rd gear gronks) and no amount of gear oil changes may fix that. You should have the CD-009 in yours so I'd venture to say that there's something else going on.

But if you want to try a fluid "fix" (more like a "let's see if this helps") stopgap measure, MT-85 is what you want.

 

I use Redline MT85 in both my street and race Zs. It's a synthetic lubricant with enough friction engineered in to allow syncros to operate at peak efficiency. The mix of MTL and MT90 was used in the past to get the same viscosity that MT85 is at right out of the bottle.

There are other choices out there, but for me, MT85 is the best alternative.

 

i wonder if the fluid has ever been changed.......may be more of a fluid issue vs synchros

 

Thank you for your input guys, I appreciate it. MT85 it is... an yes I'm hoping for a fluid cure but is not something I expect will happen, but I have to try. I have restored many a British classic car, but I'm afraid anything built after 1967 I have little knowledge on. I had a trans shop drive the car and he was not convinced the the syncro is wearing out, at least not enough to justify the expense of a repair. Maybe I'm too picky, but it just does not slide in to second like I feel it should. Do any of you have to persuade it in to second a bit?
Thanks, Pat

 

Beyond using MT85, shifting technique always helps. Heel-toe downshifting with a quick blip will help those second gear syncros.